Alright, sorry for the late reply, had to test it out so I don't waste your time.
I've found the WSE files just like you said, didn't use them while installing, left them alone now too.
Great news! Seems I no longer have red errors! It's the 'B Patch' that solved it, I think.
I can finally play an up-to-date version of Brytenwalda - Reworked, battles are playable now!
Okay hope it's not too much as a final touch some new village scenes (new to Reworked) are very laggy as in I can hardly move without eyestrain. Yes my PC is very old but any other scenes/battles I get on highest detail with barely a stutter, so I guess something in some specific scenes is causing the unbearable lag. One example I'm sure of is the scene with the village fort with a couple of buidlings and a little watchtower also village's housing is outside along a river, as far as I remember.
In short, is there any way for me to revert some village scenes, or just replace them with generic ones from Brytenwalda 1.41 vanilla or even other mods? I realize this is in no way a bug or glitch but it's the last real obstacle to having a great time with the mod. So how do I identify what scenes are for what villages on the map and then replace them? What files would I need to play around with?
Anyway, you've already answered my important questions, so thank you again for all your work on the mod and being active as much as you can on the forums. Cheers!