diff --git a/components/tachart/languages/tachartstrconsts.de.po b/components/tachart/languages/tachartstrconsts.de.po
index 86c4b38c28..e8aa939051 100644
--- a/components/tachart/languages/tachartstrconsts.de.po
+++ b/components/tachart/languages/tachartstrconsts.de.po
@@ -290,6 +290,10 @@ msgstr "Linear"
 msgid "Line series"
 msgstr "Linien-Diagramm"
 
+#: tachartstrconsts.rslistsourcestringformaterror
+msgid "The data value count in the %0:s.DataPoints string \"%1:s\" differs from what is expected from XCount and YCount."
+msgstr "Die Anzahl der Datenwerte im %s.DataPoints-String \"%s\" entspricht nicht der, die aufgrund von XCount und YCount erwartet wird."
+
 #: tachartstrconsts.rslogarithmic
 msgid "Logarithmic"
 msgstr "Logarithmisch"
diff --git a/components/tachart/languages/tachartstrconsts.fi.po b/components/tachart/languages/tachartstrconsts.fi.po
index b6a2e29f8a..941769a8d9 100644
--- a/components/tachart/languages/tachartstrconsts.fi.po
+++ b/components/tachart/languages/tachartstrconsts.fi.po
@@ -278,6 +278,10 @@ msgstr "Lineaarinen"
 msgid "Line series"
 msgstr "Viivakuvaaja"
 
+#: tachartstrconsts.rslistsourcestringformaterror
+msgid "The data value count in the %0:s.DataPoints string \"%1:s\" differs from what is expected from XCount and YCount."
+msgstr ""
+
 #: tachartstrconsts.rslogarithmic
 msgid "Logarithmic"
 msgstr "Logaritminen"
diff --git a/components/tachart/languages/tachartstrconsts.fr.po b/components/tachart/languages/tachartstrconsts.fr.po
index 0d3bb23458..e386ba854f 100644
--- a/components/tachart/languages/tachartstrconsts.fr.po
+++ b/components/tachart/languages/tachartstrconsts.fr.po
@@ -288,6 +288,10 @@ msgstr "Linéaire"
 msgid "Line series"
 msgstr "Séries de lignes"
 
+#: tachartstrconsts.rslistsourcestringformaterror
+msgid "The data value count in the %0:s.DataPoints string \"%1:s\" differs from what is expected from XCount and YCount."
+msgstr ""
+
 #: tachartstrconsts.rslogarithmic
 msgid "Logarithmic"
 msgstr "Logarithmique"
diff --git a/components/tachart/languages/tachartstrconsts.hu.po b/components/tachart/languages/tachartstrconsts.hu.po
index 079e69b6d2..7b92b19cf4 100644
--- a/components/tachart/languages/tachartstrconsts.hu.po
+++ b/components/tachart/languages/tachartstrconsts.hu.po
@@ -288,6 +288,10 @@ msgstr "Lineáris"
 msgid "Line series"
 msgstr "Vonal"
 
+#: tachartstrconsts.rslistsourcestringformaterror
+msgid "The data value count in the %0:s.DataPoints string \"%1:s\" differs from what is expected from XCount and YCount."
+msgstr ""
+
 #: tachartstrconsts.rslogarithmic
 msgid "Logarithmic"
 msgstr "Logaritmikus"
diff --git a/components/tachart/languages/tachartstrconsts.lt.po b/components/tachart/languages/tachartstrconsts.lt.po
index db2a1dba84..1d0b8efcd6 100644
--- a/components/tachart/languages/tachartstrconsts.lt.po
+++ b/components/tachart/languages/tachartstrconsts.lt.po
@@ -289,6 +289,10 @@ msgstr "Tiesinė"
 msgid "Line series"
 msgstr "Linijų sekos"
 
+#: tachartstrconsts.rslistsourcestringformaterror
+msgid "The data value count in the %0:s.DataPoints string \"%1:s\" differs from what is expected from XCount and YCount."
+msgstr ""
+
 #: tachartstrconsts.rslogarithmic
 msgid "Logarithmic"
 msgstr "Logaritminė"
diff --git a/components/tachart/languages/tachartstrconsts.pl.po b/components/tachart/languages/tachartstrconsts.pl.po
index 652d49bf3c..2290c8fbd3 100644
--- a/components/tachart/languages/tachartstrconsts.pl.po
+++ b/components/tachart/languages/tachartstrconsts.pl.po
@@ -288,6 +288,10 @@ msgstr "Liniowy"
 msgid "Line series"
 msgstr ""
 
+#: tachartstrconsts.rslistsourcestringformaterror
+msgid "The data value count in the %0:s.DataPoints string \"%1:s\" differs from what is expected from XCount and YCount."
+msgstr ""
+
 #: tachartstrconsts.rslogarithmic
 msgid "Logarithmic"
 msgstr "Logarytmiczny"
diff --git a/components/tachart/languages/tachartstrconsts.pot b/components/tachart/languages/tachartstrconsts.pot
index 3447d274d4..2539aa6343 100644
--- a/components/tachart/languages/tachartstrconsts.pot
+++ b/components/tachart/languages/tachartstrconsts.pot
@@ -278,6 +278,10 @@ msgstr ""
 msgid "Line series"
 msgstr ""
 
+#: tachartstrconsts.rslistsourcestringformaterror
+msgid "The data value count in the %0:s.DataPoints string \"%1:s\" differs from what is expected from XCount and YCount."
+msgstr ""
+
 #: tachartstrconsts.rslogarithmic
 msgid "Logarithmic"
 msgstr ""
diff --git a/components/tachart/languages/tachartstrconsts.pt_BR.po b/components/tachart/languages/tachartstrconsts.pt_BR.po
index 37429af2a3..7a67b7b49a 100644
--- a/components/tachart/languages/tachartstrconsts.pt_BR.po
+++ b/components/tachart/languages/tachartstrconsts.pt_BR.po
@@ -288,6 +288,10 @@ msgstr "Linear"
 msgid "Line series"
 msgstr "Série Linha"
 
+#: tachartstrconsts.rslistsourcestringformaterror
+msgid "The data value count in the %0:s.DataPoints string \"%1:s\" differs from what is expected from XCount and YCount."
+msgstr ""
+
 #: tachartstrconsts.rslogarithmic
 msgid "Logarithmic"
 msgstr "Logarítimo"
diff --git a/components/tachart/languages/tachartstrconsts.ru.po b/components/tachart/languages/tachartstrconsts.ru.po
index ae8cec5aac..605960b4ad 100644
--- a/components/tachart/languages/tachartstrconsts.ru.po
+++ b/components/tachart/languages/tachartstrconsts.ru.po
@@ -288,6 +288,10 @@ msgstr "Линейный масштаб"
 msgid "Line series"
 msgstr "График"
 
+#: tachartstrconsts.rslistsourcestringformaterror
+msgid "The data value count in the %0:s.DataPoints string \"%1:s\" differs from what is expected from XCount and YCount."
+msgstr ""
+
 #: tachartstrconsts.rslogarithmic
 msgid "Logarithmic"
 msgstr "Логарифмический масштаб"
diff --git a/components/tachart/languages/tachartstrconsts.se.po b/components/tachart/languages/tachartstrconsts.se.po
index b160bfb898..4a99c49674 100644
--- a/components/tachart/languages/tachartstrconsts.se.po
+++ b/components/tachart/languages/tachartstrconsts.se.po
@@ -291,6 +291,10 @@ msgstr "Linjär"
 msgid "Line series"
 msgstr "Linjediagram"
 
+#: tachartstrconsts.rslistsourcestringformaterror
+msgid "The data value count in the %0:s.DataPoints string \"%1:s\" differs from what is expected from XCount and YCount."
+msgstr ""
+
 #: tachartstrconsts.rslogarithmic
 msgid "Logarithmic"
 msgstr "Logaritmisk"
diff --git a/components/tachart/languages/tachartstrconsts.uk.po b/components/tachart/languages/tachartstrconsts.uk.po
index 2e77b764d3..4d065c3c20 100644
--- a/components/tachart/languages/tachartstrconsts.uk.po
+++ b/components/tachart/languages/tachartstrconsts.uk.po
@@ -291,6 +291,10 @@ msgstr "Лінійний масштаб"
 msgid "Line series"
 msgstr "Графік"
 
+#: tachartstrconsts.rslistsourcestringformaterror
+msgid "The data value count in the %0:s.DataPoints string \"%1:s\" differs from what is expected from XCount and YCount."
+msgstr ""
+
 #: tachartstrconsts.rslogarithmic
 msgid "Logarithmic"
 msgstr "Логарифмічний масштаб"
diff --git a/components/tachart/languages/tachartstrconsts.zh_CN.po b/components/tachart/languages/tachartstrconsts.zh_CN.po
index 781bd7f096..fabd190f12 100644
--- a/components/tachart/languages/tachartstrconsts.zh_CN.po
+++ b/components/tachart/languages/tachartstrconsts.zh_CN.po
@@ -289,6 +289,10 @@ msgstr "线性的(Linear)"
 msgid "Line series"
 msgstr "折线图系列"
 
+#: tachartstrconsts.rslistsourcestringformaterror
+msgid "The data value count in the %0:s.DataPoints string \"%1:s\" differs from what is expected from XCount and YCount."
+msgstr ""
+
 #: tachartstrconsts.rslogarithmic
 msgid "Logarithmic"
 msgstr "对数的"
diff --git a/components/tachart/tachartstrconsts.pas b/components/tachart/tachartstrconsts.pas
index d7ccd5fc34..a618be911c 100644
--- a/components/tachart/tachartstrconsts.pas
+++ b/components/tachart/tachartstrconsts.pas
@@ -71,6 +71,9 @@ resourcestring
   // Chart sources
   rsSourceCountError = '%0:s requires a chart source with at least %1:d %2:s value(s) per data point.';
   rsSourceCountError2 = 'This %0:s instance must have at least %1:d %2:s value(s) per data point.';
+  rsListSourceStringFormatError = 'The data value count in the %0:s.DataPoints '+
+    'string "%1:s" differs from what is expected from XCount and YCount.';
+
 
   // Transformations
   tasAxisTransformsEditorTitle = 'Edit axis transformations';
diff --git a/components/tachart/tacustomsource.pas b/components/tachart/tacustomsource.pas
index 2782948b84..1658662ef3 100644
--- a/components/tachart/tacustomsource.pas
+++ b/components/tachart/tacustomsource.pas
@@ -73,6 +73,7 @@ type
   EEditableSourceRequired = class(EChartError);
   EXCountError = class(EChartError);
   EYCountError = class(EChartError);
+  EListSourceStringFormatError = class(EChartError);
 
   TChartValueText = record
     FText: String;
diff --git a/components/tachart/tasources.pas b/components/tachart/tasources.pas
index 061a7332d6..b41fb8c2db 100644
--- a/components/tachart/tasources.pas
+++ b/components/tachart/tasources.pas
@@ -38,6 +38,7 @@ type
   protected
     function GetCount: Integer; override;
     function GetItem(AIndex: Integer): PChartDataItem; override;
+    procedure Loaded; override;
     procedure SetXCount(AValue: Cardinal); override;
     procedure SetYCount(AValue: Cardinal); override;
   public
@@ -258,7 +259,10 @@ type
   TListChartSourceStrings = class(TStrings)
   strict private
     FSource: TListChartSource;
+    FLoadingCache: TStringList;
     procedure Parse(AString: String; ADataItem: PChartDataItem);
+  private
+    procedure LoadingFinished;
   protected
     function Get(Index: Integer): String; override;
     function GetCount: Integer; override;
@@ -266,6 +270,7 @@ type
     procedure SetUpdateState(AUpdating: Boolean); override;
   public
     constructor Create(ASource: TListChartSource);
+    destructor Destroy; override;
     procedure Clear; override;
     procedure Delete(Index: Integer); override;
     procedure Insert(Index: Integer; const S: String); override;
@@ -284,7 +289,10 @@ end;
 
 procedure TListChartSourceStrings.Clear;
 begin
-  FSource.Clear;
+  if not (csLoading in FSource.ComponentState) then
+    FSource.Clear
+  else
+    FreeAndNil(FLoadingCache);
 end;
 
 constructor TListChartSourceStrings.Create(ASource: TListChartSource);
@@ -293,6 +301,12 @@ begin
   FSource := ASource;
 end;
 
+destructor TListChartSourceStrings.Destroy;
+begin
+  inherited;
+  FLoadingCache.Free;
+end;
+
 procedure TListChartSourceStrings.Delete(Index: Integer);
 begin
   FSource.Delete(Index);
@@ -306,29 +320,49 @@ begin
   fs := DefaultFormatSettings;
   fs.DecimalSeparator := '.';
   with FSource[Index]^ do begin
-    Result := Format('%g', [X], fs);
+    Result := '';
+    if FSource.XCount > 0 then
+      Result += Format('%g|', [X], fs);
     for i := 0 to High(XList) do
-      Result += Format('|%g', [XList[i]], fs);
+      Result += Format('%g|', [XList[i]], fs);
     if FSource.YCount > 0 then
-      Result += Format('|%g', [Y], fs);
+      Result += Format('%g|', [Y], fs);
     for i := 0 to High(YList) do
-      Result += Format('|%g', [YList[i]], fs);
-    Result += Format('|%s|%s', [IntToColorHex(Color), Text]);
+      Result += Format('%g|', [YList[i]], fs);
+    Result += Format('%s|%s', [IntToColorHex(Color), Text]);
   end;
 end;
 
 function TListChartSourceStrings.GetCount: Integer;
 begin
-  Result := FSource.Count;
+  if not (csLoading in FSource.ComponentState) then
+    Result := FSource.Count
+  else
+  if Assigned(FLoadingCache) then
+    Result := FLoadingCache.Count
+  else
+    Result := 0;
 end;
 
 procedure TListChartSourceStrings.Insert(Index: Integer; const S: String);
 var
   item: PChartDataItem;
 begin
+  if csLoading in FSource.ComponentState then begin
+    if not Assigned(FLoadingCache) then
+      FLoadingCache := TStringList.Create;
+    FLoadingCache.Insert(Index, S);
+    exit;
+  end;
+
   item := FSource.NewItem;
-  FSource.FData.Insert(Index, item);
-  Parse(S, item);
+  try
+    Parse(S, item);
+    FSource.FData.Insert(Index, item);
+  except
+    Dispose(item);
+    raise;
+  end;
   FSource.UpdateCachesAfterAdd(item^.X, item^.Y);
 end;
 
@@ -350,20 +384,33 @@ var
 var
   i: Integer;
 begin
+  // Note: this method is called only when component loading is fully finished -
+  // so FSource.XCount and FSource.YCount are already properly estabilished
+
   parts := Split(AString);
   try
-    if (FSource.XCount = 1) and (FSource.YCount + 3 < Cardinal(parts.Count)) then
-      FSource.YCount := parts.Count - 3;
+    // There should be XCount + YCount .. XCount + YCount + 2 (for Color and Text)
+    // parts of the string
+    if (Cardinal(parts.Count) <> FSource.XCount + FSource.YCount + 2) then begin
+      if Length(AString) > 20 then AString := Copy(AString, 1, 20) + '...';
+      raise EListSourceStringFormatError.CreateFmt(
+        rsListSourceStringFormatError,
+        [IfThen(FSource.Name <> '', FSource.Name, FSource.ClassName), AString]);
+    end;
+
     with ADataItem^ do begin
-      X := StrToFloatOrDateTimeDef(NextPart);
-      if FSource.XCount > 1 then
+      if FSource.XCount > 0 then begin
+        X := StrToFloatOrDateTimeDef(NextPart);
         for i := 0 to High(XList) do
           XList[i] := StrToFloatOrDateTimeDef(NextPart);
+      end else
+        X := NaN;
       if FSource.YCount > 0 then begin
         Y := StrToFloatOrDateTimeDef(NextPart);
         for i := 0 to High(YList) do
           YList[i] := StrToFloatOrDateTimeDef(NextPart);
-      end;
+      end else
+        Y := NaN;
       Color := StrToIntDef(NextPart, clTAColor);
       Text := NextPart;
     end;
@@ -384,10 +431,22 @@ end;
 
 procedure TListChartSourceStrings.SetUpdateState(AUpdating: Boolean);
 begin
-  if AUpdating then
-    FSource.BeginUpdate
-  else
-    FSource.EndUpdate;
+  if not (csLoading in FSource.ComponentState) then
+    if AUpdating then
+      FSource.BeginUpdate
+    else
+      FSource.EndUpdate;
+end;
+
+procedure TListChartSourceStrings.LoadingFinished;
+begin
+  // csLoading in FSource.ComponentState is already cleared
+  if Assigned(FLoadingCache) then
+    try
+      Assign(FLoadingCache);
+    finally  
+      FreeAndNil(FLoadingCache);
+    end;
 end;
 
 { TListChartSource }
@@ -781,6 +840,12 @@ begin
   Notify;
 end;
 
+procedure TListChartSource.Loaded;
+begin
+  inherited; // clears csLoading in ComponentState
+  (FDataPoints as TListChartSourceStrings).LoadingFinished;
+end;
+
 { TMWCRandomGenerator }
 
 function TMWCRandomGenerator.Get: LongWord;
diff --git a/components/tachart/test/SourcesTest.pas b/components/tachart/test/SourcesTest.pas
index 42f60ea475..fdab6a903e 100644
--- a/components/tachart/test/SourcesTest.pas
+++ b/components/tachart/test/SourcesTest.pas
@@ -369,9 +369,9 @@ begin
   oldSeparator := DefaultFormatSettings.DecimalSeparator;
   try
     DefaultFormatSettings.DecimalSeparator := ':';
-    FSource.DataPoints.Add('3:5');
+    FSource.DataPoints.Add('3:5|?|?|');
     AssertEquals(3.5, FSource[0]^.X);
-    FSource.DataPoints[0] := '4.5';
+    FSource.DataPoints[0] := '4.5|?|?|';
     AssertEquals(4.5, FSource[0]^.X);
   finally
     DefaultFormatSettings.DecimalSeparator := oldSeparator;
@@ -453,9 +453,81 @@ procedure TListSourceTest.Multi;
 begin
   FSource.Clear;
   AssertEquals(1, FSource.YCount);
+  AssertEquals(1, FSource.YCount);
+
   FSource.Add(1, 2);
   FSource.YCount := 2;
   AssertEquals([0], FSource[0]^.YList);
+
+  FSource.SetYList(0, [3]);
+  AssertEquals(3, FSource[0]^.YList[0]);
+
+  FSource.DataPoints.Add('1|2|3|?|t');
+  AssertEquals(1, FSource.XCount);
+  AssertEquals(2, FSource.YCount);
+  AssertEquals(1, FSource[1]^.X);
+  AssertEquals(2, FSource[1]^.Y);
+  AssertEquals(3, FSource[1]^.YList[0]);
+
+  try
+    FSource.DataPoints.Add('10|20|30|40|?|');
+  except
+    on E: Exception do
+      AssertTrue('Too many values', E is EListSourceStringFormatError);
+  end;
+  AssertEquals(2, FSource.Count);
+
+  try
+    FSource.DataPoints.Add('10|20|?|');
+  except
+    on E: Exception do
+      AssertTrue('Too few values', E is EListSourceStringFormatError);
+  end;
+  AssertEquals(2, FSource.Count);
+
+  try
+    FSource.DataPoints.Add('10|20|30|?');
+  except
+    on E: Exception do
+      AssertTrue('Text field missing', E is EListSourceStringFormatError);
+  end;
+  AssertEquals(2, FSource.Count);
+
+  try
+    FSource.DataPoints.Add('10|20|30|t');
+  except
+    on E: Exception do
+      AssertTrue('Color field missing', E is EListSourceStringFormatError);
+  end;
+  AssertEquals(2, FSource.Count);
+
+  try
+    FSource.AddXYList(4, []);
+  except
+    on E: Exception do
+      AssertTrue('Empty YList', E is TListChartSource.EYListEmptyError);
+  end;
+
+  FSource.Clear;
+  FSource.XCount := 2;
+  FSource.YCount := 3;
+  FSource.AddXListYList([1, 2], [3, 4, 5]);
+  AssertEquals(2, FSource.XCount);
+  AssertEquals(3, FSource.YCount);
+  AssertEquals(1, FSource[0]^.X);
+  AssertEquals(2, FSource[0]^.XList[0]);
+  AssertEquals(3, FSource[0]^.Y);
+  AssertEquals(4, FSource[0]^.YList[0]);
+  AssertEquals(5, FSource[0]^.YList[1]);
+
+  FSource.DataPoints.Add('10|20|30|40|50|?|t');
+  AssertEquals(10, FSource[1]^.X);
+  AssertEquals(20, FSource[1]^.XList[0]);
+  AssertEquals(30, FSource[1]^.Y);
+  AssertEquals(40, FSource[1]^.YList[0]);
+  AssertEquals(50, FSource[1]^.YList[1]);
+
+  (*
   FSource.SetYList(0, [3, 4]);
   AssertEquals('Extra items are chopped', [3], FSource[0]^.YList);
   FSource.DataPoints.Add('1|2|3|4|?|t');
@@ -478,6 +550,7 @@ begin
   except on E: Exception do
     AssertTrue('Empty YList', E is TListChartSource.EYListEmptyError);
   end;
+  *)
 end;
 
 procedure TListSourceTest.SetUp;
diff --git a/components/tachart/test/test.lpi b/components/tachart/test/test.lpi
index b0007fe33e..9ee1a8896b 100644
--- a/components/tachart/test/test.lpi
+++ b/components/tachart/test/test.lpi
@@ -24,9 +24,6 @@
     </BuildModes>
     <PublishOptions>
       <Version Value="2"/>
-      <IgnoreBinaries Value="False"/>
-      <IncludeFileFilter Value="*.(pas|pp|inc|lfm|lpr|lrs|lpi|lpk|sh|xml)"/>
-      <ExcludeFileFilter Value="*.(bak|ppu|ppw|o|so);*~;backup"/>
     </PublishOptions>
     <RunParams>
       <FormatVersion Value="2"/>
@@ -85,7 +82,7 @@
     </CodeGeneration>
   </CompilerOptions>
   <Debugging>
-    <Exceptions Count="4">
+    <Exceptions Count="5">
       <Item1>
         <Name Value="EAbort"/>
       </Item1>
@@ -98,6 +95,9 @@
       <Item4>
         <Name Value="TListChartSource.EYListEmptyError"/>
       </Item4>
+      <Item5>
+        <Name Value="EListSourceStringFormatError"/>
+      </Item5>
     </Exceptions>
   </Debugging>
 </CONFIG>