Song Stone Short

TL;DR: TWW/TP have a bit flawed memory management making it vulnerable for fragmentation. Storing things can keep stuff loaded over the boundaries of a room creating further fragmentation. If there is not a big enough memory space to fit a new actor in, the game can not load it and it doesnt appear. Due an additional oversight this permanently creates a dead entry in the internal actor list, so from this point on no instance of this actor will ever appear again until console reboot

Cutscenes that rely on controlling/animating actors will fail to start if they need an actor that got corrupted