MFiX 22.1 should be released before the end of March. However this will not fix all of the problems you are seeing, just some of the minor side-effects (“error saving file”).
I suggest you try running with vglrun (virtual GL). See also this thread:
https://mfix.netl.doe.gov/forum/t/working-difference-between-mfix-19-3-1-and-20-1-2/1798/3