Just a note, after reading about others getting dosemu2 up and running, I was able to get it going on Mystic. Works like a charm!
While I'm not running Mystic in a Docker container, I was able to crib Deadbeatz's rundoor.sh script and dosemu folder to make it all work:
https://github.com/deadbeatz/mystic_a45
Only LORD and DARNKESS running so far, but a big win personally for me :)
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|07Ã[|08..|11The Drunken Gamer BBS|08.....|07]´ |07À[|08..|03TheDrunkenGamer.com:8888|08..|07]Ù
--- Mystic BBS v1.12 A47 2020/09/12 (Linux/64)
* Origin: The Drunken Gamer BBS (21:4/158)