No endless loops, just lots of CtDs.
Most of them are when I end a turn. I was also occasionally getting CtDs from my FoL Priests' Summon Animal spell (I replaced summon tiger with this, but I think it is too strong so it may become a druid spell), but I think I fixed that. (This spell randomly selects one from a list of animal units; I had forgotten that the index is 1 less than the length, so it never summoned a wolf and it crashed when it was supposed o summon a gorilla)
For a moment I thought I'd forgotten to include his new improvements, but then I realized that I was looking in the unmodded version. The file looks correct when I'm in the right folder.
I wonder if adding Creation, Dimensional, Force, and Ice Nodes and resources could have something to do with it? (For now they all look like Air mana/nodes, and I haven't added their spells. Dimensional does pass on duration-boosting promotions to summons though, and seems to be working fine.) I also made most unique features provide mana, and made citadels and enclaves act as cities.
Edit: Now I've made it 97 turns without a CtD (the furthest I've gotten since including marnok mod, about as long as I often made it before incorperating this), but seem to be having a WoC instead. Maybe going down to a tiny map helps. (With my changes, Charadon of the Sheaim is a very good combo.) Edit: When I left and reloaded a save from the turn before the WoC it still WoCed. When I went back to a save 6 turns sooner and made a few different decisions (researching infernal pact instead of arcane lore, building the Stigmata instead of an Academy, training a ritualist instead of a pyre zombie, not attacking a hippus city and losing Rosier and a succubus, ect) I got no WoC, but did get a CtD at tune 99.