Working on the EdiSyn Preferences Window. I saw already before that a dialog style window has some problem (every redraw makes the window larger). In the past I just changed the window to sizeable and set tight Contraints (Min=Max), then it worked well. Today I had some time to look deeper into the stuff. I put a MUIC_Group into the Window as first item and On Layout I set the size of this item to the inner size of the window. But this Group has a Border (MUIA_InnerXXX) so a solution seemd to remov this border, but then MUI draws 1 pixel over the window border. So I had to add a 1 pixel border, but then I must calculate the inner size for the drawing. Now it works. As nice side effect now the (visible) offset of the item to the window border is gone, which is nice (visible in the left upper order of the window). The Groupbox (which is directly mapped to the MUI Groupbox with the Title) works very nicely, there I also need this offset value, so it had an additional use.