@nina_kali_nina maybe it would also be possible to get twin going for something with windowing: https://github.com/cosmos72/twin

MGR seems a lot fancier though

How is the hardware support of Fiwix? I don't know if DOSBox can do any device pass-through, DOSEMU(2) does have some support for that so you could possibly use hardware that lacks Fiwix drivers but does have DOS drivers.