It's a 128x96 8bpp bitmap file. It assumes that the default X16 palette is used. There are some tools to create those. We have a discussion about a standardised bitmap file format on the Discord. Maybe I'll change to that later.
It would also be nice if the emulator could create these thumbnails directly, like pressing ctrl+T...
The thumbnails have to be named ".THUMB.ABM" (notice the decimal point at the start of the name).
Also there is a ".META.INF" file which contains title, author and description.
Right now it assumes that there is a PRG named exactly the same as the directory name. So in your case this would work.ahenry3068 wrote: ↑Tue Nov 14, 2023 9:27 am Also what if there is more than 1 prg in the directory. In HANGMAN I have HANGMAN.PRG and CREDITS.PRG
There of course is the case where multiple PRGs are in one directory, each of them a self-contained program. I have to think about how to approach that...
I also haven't checked if Basic programs will work. That's next on the list.