> There is a website that has many PD Apple IIGS games, but they are all in .BXY, or
> .BSQ formats which MAME can't read. I am running Windows, and have CiderPress, which
> can read .BXY, but not .BSQ. When I use CiderPress, it turns .BXY images into 800KB
> images in .PO format, which MAME can't read either. I am looking for a way to get the
> games into a format MAME can read. The only format MAME can read appears to be .2MG
> 801KB in size.
unless I'm mistaken the first two of those aren't disk image formats, but just a container containing the compressed assets for the game like a zip or a 7z file? (it's also possible they contain a disk image rather than loose files, but obviously they could contain anything)
if so, not surprising MAME can't run them
.PO should be a disk image format tho, not sure why MAME doesn't support that.
for PD software such scenarios aren't too uncommon as you were expected to extract the archives on the original machines, a lot of Amiga software is compressed and distributed as LHA for similar reasons.