About SpinEdit

I use multiple advspinedits on the form.
If the cursor is over an unselected component, the value can be changed with the wheel. Can only the selected component change the value?

Assign this:

procedure TYourForm.ValidateSpinEditsWheelMovement(Sender: TObject; Shift: TShiftState;
  MousePos: TPoint; var Handled: Boolean);
begin
  Handled := not TAdvSpinEdit(sender).Focused;
end;

to all your AdvSpinEdit's OnMouseWheelDown and OnMouseWheelUp events.