I've fixed the clipping problem, but I'm not sure that it's very efficient. I'm creating and disposing regions everytime I need to refresh the icon display. Not problems on the G3, but things might be different on a 6100/60 :p
I've also fixed a problem with the zooming, but I'm still using DrawString to display the zoom text, instead of using a control (which is Appearance Manager savvy and respects the enabled/disabled state of the windwo).