Came across a bug where no matter how many maps I passed through, enemy monster levels stayed the same (in my case, at the 25-35 range), and wouldn't scale up as they should. The bug only fixed itself after I went to the Outpost and back, with monsters immediately going back to their appropriate levels.
Played on GZDoom g2.2.0, DRLA 1.05 and the latest 1.05-compatible version of DRPG as compiled by Yholl.