Thanks! That's so cool! Hmm, I honestly don't really know much about portmaster. I know GM has a linux export, but I don't have linux personally so I cannot test it. The source code is on github (linked at the top of the page). Maybe it runs from that?
You may visit http://portmaster.games/ to learn more about the project :)
We have a packager called gmloader which helps to run the data.win on arm devices. Have gotten it to work and so far it is running great in internal testing!