You can try icy draw - I moved it to here (0.3.0 is the current version):

https://github.com/mkrueger/icy_tools/releases/tag/0.0.1

Runs on linux/osx and windows.

It can draw 80x25 fixed size screens, supports all common (and many uncommon :)) formats - it should be able to generate nearly optimal .ans files.

Has tons of options - it's a modern heavy weight (multi document) program.

Regards
Mike

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