@folly I'm still working silly hours so I haven't had any time to tinker, but I saw that you managed to crack the Acorn Electron!
I wanted to look at how to play Metal gear 1 and 2 on lr-bluemsx to use Retroachievements. The games run fine through rom files but the saving function doesn't work as you need a separate cassette which the emulator doesn't seem to emulate.
I hope you enjoy the work and earn a lot of money with these many hours of work.
Indeed that Acorn stuff works really great, you should try it out.
I also added the same disc autoboot in the xbeeb and xmaster now (bbcmicro).
I think .cas files should work on lr-bluemsx.
I can have a look at that, perhaps I can figure it out.
Not knowing much about Retroachievements have a look at that too.
@supercatfooz Update: I just found an HDF file that seems to work fine, making the two .dim files I have obsolete. I'd still like to know if multi-disk mounting is possible for the future, though! (plus it'll help whoever else happens to have this problem)
@Pyjamarama You can save your controller settings for that game or across the whole core. Those options are in the control menu in the hotkey+X retroArch menu, right above where you edit the control inputs.
That's a shame. I was hoping it was something I could fix on my own. I do love my Japanese computers. I'm glad to see that an official Retropie guide for the PC-88 emulator showed up within the past few months at least.