Hello!
I made this emulator compatible with U3.
My english isn't so good to talk more about what I made, but i'll try hehe
Well... my launcher arrange all the paths in vba.ini to folders like "rom" and "save" on U3:\Documents\VisualBoyAdvance...
Download: http://www.4shared.com/file/56322337/9b982857/VisualBoyAdvance_172_U3.html
EDIT: Now the emulator deletes the unused registry key after closed!
Thanks thibeaz