You need to show me your Profile Details that has every mod you want to play with activated. Having Gameplay - Difficulty and Story being the only activated mod will of course show missing models because I took them all out (with the exception of all the new enemy models SC created) in the 2.37 update. My guess is that you still had Gameplay - Difficulty and Store loaded above Field Models - Main Characters after you updated to 2.37, which causes the bad overwrite.
There is a new load order in STEP 5 of the tutorial that shows a complete list. I think this is just a case of a load order mistake, but to be fair, I've pushed out a lot of updates recently that makes the process a little confusing. Once I hit the final updates, it will all be easy again.
