I was able to get it running on my steamdeck using Proton 7.0-6 I didn't even use Wine at all. Hope that helps
I don't use Steam, but nonetheless I've tried with several versions of GE-Proton to no avail. :(
Thanks for your help, anyway. :)
I was able to export to Linux, so that's now available. But I haven't tested it yet. Sorry you had all this trouble!
Unfortunately the native Linux build crashes at launch. If you want I could provide the error logs (but I'm not sure whether you have any way to debug it).
Thanks again for your effort. :)