Unfortunately trying to just change the screen resolution broke too many of the effects, id have to rewrite too much. I might do so later, perhaps add a scaling routine
Im running it on a fairly modern laptop , so i dont know exactly why its not working for you as its not set to run full screen. But yes 320x200 is defiantly not standard :-P
I was just playing around with an image and ended up creating a whole demo stemming from the 320x200 image size. And at 320x200 it creates a very retro feel
