I know this thread died long ago, but I figured I might as well post that I think I solved the mystery when sitting back down to play some Skyrim today. Turns out I'm an idiot and improperly installed RCRN with MO, a mistake I rectified. In the process, I undid STEP's setup of the enblocal.ini. Oops. With both problems fixed, Skyrim has so far run like a dream with no problems thusfar. However, I accidentally BOSS'd my "Improved Close-Faced Helmets_Legendary.esp" (from Weapons and Armor Fixes) out of load order and can't seem to figure out where it goes. STEP 2.2.8 (version I'm on, haven't updated yet) probably explains where to put it, but I can't figure it out after looking back through the instructions. I'm probably just blind.
