The bug happens when you’re trying to re-parent objects using the Parent feature. Lets say for example, ‘Model A’ to ‘Folder 1’, ‘Part 1’ to ‘ServerStorage’, and so on. It would then have, for example, ‘ReplicatedStorage’ placed inside ‘Workspace’, then a pause, then crashes.
How the heck do services get parented to the workspace? Good game.
I haven’t had this problem, but I don’t want to risk trying it. Regardless, the parent property is valuable and saves time having to drag things up a list.
I re-created your game hierarchy (Base Models folder, 2 models, and Baseplate+Part), but was not able to reproduce the issue. If you re-open the place, does it still happen? Can you add a folder+part on an empty baseplate and get this to happen, or is it only that place? Also, does this happen when you disable all plugins?