So apparently if you have 2 identical versions of UE4 open and try to save one, it has a fit and at least for me, broke something fundamental (I think) in the StandardMacros. As you can see from the screenshots, the isValid node is returning false in my animation BP, when the character’s skeletal mesh is definitely using that BP. This has broken a lot of functionality in my game, but the main issues stem from these two macros. If anyone has experienced anything similar or has ideas to try, I’m more than willing to try, because it’s giving me a serious headache.