The original GFA editor was not tasking freindly. But there is a patch, ironically called 'bastard' that will allow the old editor to run on MiNT. I can run the old editor on my Hades in 1280x1024 in 256 colors or my TT030 on the crazydots card. It's not perfect, there are some visual glitches here and there but one can get by without rebooting. I only recommend this approach for GFA fanatics, who are dead set on using the original editor. ;o)
Yes, there is also a new GEM Editor which attempts to solve all these problems. It has all the same basic features, plus integrated compiler support, so it works alot like HBasic. Enter the code, hit compile. It even looks alot like the old one. There's an updated linker and compiler as well and a new library which is system clean. Plus it's all free.