OK, finally result as I can now more or less run anything FG99 on the QI. Starting up is still a bit of a hack (see below) but I think that can be fixed. Downside currently is that it requires minor hardware surgery (cutting the GS track) and FG99 won't run on the classic TI without adding a switch of some sort to bypass the mod:     While I am still working on a software solution (CPLD update), I have taken Ralph's suggestion and added a RC delay to GS*. After extensive tes