Yeah it does self damage a lot I don't think its a very useful weapon its more a cool weapon an additional touch to weapons I suppose.
The alien gun use to make the player pop up just a bit and takes damage. I learned how to pulloff alot from observing the scripts that make the push happen. Kex is a brilliant thing.
I really like kex so far in any format xD It is responsible for bringing back two of my favorite games (soon to be 3). And I mean like top 3 games so a big thing for me and gave them both editors. I still find myself in Doom 64 ex these days lol. To me it has outlasted BD64 not a knock on BD64 though that mod is fun as hell and on zandronum mp servers is great BD64 is pretty good for a great arcade D64 experience staying somewhat original Heavy Metal Doom 64. Even started a few maps for it also. I just think Doom 64 EX is the true version because it stays nearly identically true. I don't even have to go over kex when it comes to doing Turok. Nothing short of greatness

I know you have been looking at kex in full and man it can do a lot of things its a brilliant engine yeah just like you said.
Nice to see you i'm rambling though lol.