Here's a lead for a new program that might be of use to help with VGA support. (But I haven't heard anything about it yet, so you might want to do a backup first!)
http://www.freewareppc.com/utilities/ozvga.shtml
The lone comment says it's better than seVGA, so maybe it's worth trying.
Edit: It now shows up also at
http://www.pocketpcfreewares.com/en/index.php?soft=1227
with some more description.