Old quake 3 format, huh, such a nostalgia... I remember using MD2 (even older) in one of my old games... for modeling I got a md2 blender extension that was pretty neat...
So, it seems that there's a MD3 extension in blender as well: https://forums.duke4.net/topic/5358-blender-27-md3-export-script/page__st__60__p...
Why don't you try Tesseract or Cube 2: Sauerbraten??? Both are open source and easy? They've better graphics too(Tesseract has global illumination, that works even on Intel IGPUs). (It'll be better than Easy FPS editor)
I don't know much about Cube2/Tesseract but it's not very customizable without programming is it? I can script, sure, but I'm not a game programmer. My hope with eFPSe is I could create retro games pretty easily. I like a lot of its flexibility (room over room, true 3D spaces, no code weapons and enemies, built in custom object editor for angled walls, etc) but it's oddly restrictive in some areas (importing models, no ability to create secrets built-in, doors can only be on tiles with nothing on layers above or below it)
Cube 2 and tesseract require less to no code depending on the maps and active stuff, you won't be needing to code the movement, enemies, or many other things, however you can still add cubescript (very easy). It supports many models like md2, md3, md5(they're providing the fixed exporter for blender too), iqm. While tesseracts supports gltf and objs too. Both have better graphics than eFPS and can be used to make many games. You can even make a RPG or a GTA like game.(Cube and tesseracts map editors are the best I've seen)
