We're not against having MadMapper on Linux, but porting to a new platform takes a lot of time to get right, and we're not sure it's worth the cost commercially yet.
However, we've ran some tests using MadMapper's Windows version on the Steam Deck running Steam OS / Arch Linux using the Proton compatibility layer.
While MadMapper started directly using the latest Proton (which is very impressive considering the number of dependencies and Windows-specific tricks we use on the Windows version of MadMapper) with pretty good engine performance, the user-interface ran very slow and the software was not very usable, at least on the Deck's low-power APU.
As a comparaison, MadMapper ran flawlessly on a Windows 11 installed on a SD-card on the same Steam Deck.
However, I would suggest you try the same on a Desktop computer, using Steam which comes standard with the latest Proton and facilitates software installation.