I can confirm your issue in design mode under XP. I did not fully go into the details, but the issue must be related to the fact that these components do not store their width and height in the lfm file. No idea why this bug does not show up in newer windows versions.
These are the modifications you have to apply to "ubarcodes.pas":
type
TLazBarcodeCustomBase=class(TGraphicControl)
..
published
...
property Width; // add at end
property Height; // add at end
end;
constructor TLazBarcodeCustomBase.Create(AOwner: TComponent);
begin
inherited Create(AOwner);
FBackgroundColor:=clWhite;
FForegroundColor:=clBlack;
FStrictSize:=true;
Width := 64; // add
Height := 64; // add
end;
Unfortunately, this does not entirely fix the component because there is also a range overflow error which, however, is suppressed in the default compiler settings. I did not have time to look into this one, yet.