ControlSetText CorelDraw Problem

[PuzzledGreatly]

I'm trying to use ControlSetText to change a Corel Photo-Paint X6 control. I can set the text (the control's name is Edit1). But Photo-Paint carries on behaving as if the text has not changed. So for example, the eraser's size is 40 and I change the eraser edit control to 400 Photo-Paint works as if the value is still 40. How to get iy to see the change? I've tried setting the focus to the control and sending {enter} but this hasn't worked. Any other ideas? Thanks.