So i've been making this level and suddenly i get an error message and all the wallconstruction thing si've put in the level stop being selectable. The ones that are selecteable causes an error message when i try to select them. My question is thus: if i want to protect myself from the editor removing everything i've done, which folders am i supposed to backup, i get confused because my mod has a folder in at least three different places and i have no idea which one to save.