I asked about the possibility of adding this event about a year ago (and originally asked nearly 4 years ago). Is this a dead issue?
Is there a possibility that you'll might add a new event in TsTrackBar called “OnChanging”. TRzTrackBar has this event and it is very handy. The event code is:
procedure TForm1.RzTrackBar1Changing(Sender: TObject; NewPos: Integer; var AllowChange: Boolean);