Yay, I got it running!
Decompressed the archive onto my A1200 hard drive, navigated to the directory containing the executable and ran it.
There was a scary moment when I copied the executable to a floppy and wondered why nothing happened when I ran it on my A500.
Ah, but then I realized it wasn't standalone and copied all the rest of it over too.
I must admit, it's quite impressive - even at this stage.
My gaming experience has never really advanced much beyond the Atari VCS, and getting this fired up has got me thinking just how addictive some of those games were...
Well enough about that. It occured to me after I'd had it running a while that I didn't get a screenshot. So, in the best EAB Competition tradition, here it is!
00000 
PS. I'll have a look at the code tomorrow to see how it was done...