the vga has horizonal jitter, quite bad. no way to adjust out. somebody suggested plugging a spare vga cable into the vga input on the converter board. that reduced it by 90%. the game works ...

IBM introduced the second-generation Enhanced Graphics Adapter (EGA) (Fig. 2) in 1984 that superseded and exceeded the capabilities of the CGA. The EGA was then superseded by the VGA standard in 1987.