Yeah. It is fun. I like weapons the most, because they are looking good and sound punchy.
Btw this engine is really junky if it allows making melee enemies only in a way, that they are not indicating their attack and also that attack looks more like shooting from machine gun in very close range. And even ranged enemies works weird. I was interested in playing with this engine, but if it's that junky, I will pass.
Also on the side note. Everybody are calling games, created in RGM "Doom-like", but Doom allows you to not only move forward, down, left, right, but also up and down. So RGM is more like "wolfenstein 3D-like" game engine.