You could try changing the zplane position of the controls (in the ui editor: Arrange>>Control ZPlane Order; programmatically: ATTR_ZPLANE_POSITION). That will influence the drawing order. But it's not predictable as to whether this will fix it or not. In my machine, it did not.
You could also try recreating that numeric control I mentioned in my previous post. (It was the topmost from the two in the bottom left) This is also unpredictable, but it's the only thing that worked for me.
Luis
