Ok, I'm back... and I apologize for not commenting on this thread for a long time, but there has been some real life drama for me, which I'm not sure yet how it will shake out or what it means... but it's been taking most of my evenings, so I haven't had the opportunity to really catch up with any board, sorry.
However I want to thank Prowler for his on going attempts to save data for the Amiga community; he's truly gone above and beyond for what was really just 3 discs missing from the Amiga Magazine Rack... and I can confirm they all now work under WinUAE and the default A1200 configuration now. That includes the Gunbee F-99 which after the last round of poking, works directly from the file as it should. Having loaded it though now, and having been spoiled by the MAME version of Bells And Whistles upon which it's based, I probably should have left it as an unachieved dream... it's disappointingly slow to my modern eyes now :P
Regarding the three other discs, there's really no need to waste time on them, unless you want to the challenge or to do a personal favour for me; it's not the end of the world if I don't get my Pinball high scores back, or a specific game save from when I first beat Ultima V
Besides which, and astoundingly when I played Demon I beat the highscore it took me a year to get way back when on my third go today... it's nice to know that not everything in my head has aged and decayed over the intervening years!