well, that's bad.
Can you try booting without vga to start, and run vga under the testbios emulator (see util/testbios) and let us know if that works?
I don't think that will help much. The via video bios is known not to work under the emulator. [Issue54] That's why the via code does the drop back to 16-bit trick and runs the vbios natively.
-- Richard A. Smith