I've tried some of these (changing .vdk to .dsk), but always get the ?IV ERROR. I start the core - change Machine to Dragon 32 - change Cart Slot to Disk (DOS Plus appears) - mount disk - type DIR = IV ERROR
Can you name one disk which works for you from that archive? I'll try it just to make sure. Couple I've tried already: Handicap, Hunchback.
The thing is I only get a green screen when switching from CoCo2 to Dragon 32 or 64, which means maybe that it's because it needs the bios (boot.rom)
for Dragon 32/64 maybe?
On my machine the green screen only happens when I change the Cart Slot. Before that I can flip between Coco2 / Dragon 32 /Dragon 64 freely. I suppose if we needed boot.rom for this core nothing would start at all (also the old version didn't require it). This seems more like a bug...but I don't know really, the devs can clear that one up.
@alanswx: on Coco2 I've tried 3D Brick Away, 3D Space War, Bagitman, Arkanoid, Bedlam and some other ones.