Compiling TextEditor from Erel (unmodified) under XP results in a Desktop-Executable, which looks good.
Compiling the same source under VISTA results in a Desktop-Executable with a scrollbar 2/3 of the size compared with the XP-Version. The scrollbar is much smaller and the windows frame (glass) seems to reside over it.
I've discussed this issue with Erel before here http://www.b4x.com/forum/showthread.php?t=530 but it still exists. Unfortunately you don't actually get the desktop client area requested in either XP or Vista althought the device is fine. You need to adjust the control positions or change the form size.