Situation: Sleeping in a bed causes a quest update, which moves the player to another location.
Problem: Game freezes on loading moveto destination.
First try: Using GameMode instead of MenuMode for triggering the quest update. Didn't work.
Second try: Used a timer to delay quest update for a second. Didn't work.
Third try: Added a scripted ability to the player when sleeping in bed, which triggers the quest update. This worked.
Why? I've got no idea. In neither case the objects itself did anything. They only triggered the quest update, which then moved the player. Triggering the update per hand (setstage command) also worked flawlessly. But whenever triggered by an object (I've even used a nearby activator for testing purposes), game freeze. Unless the target destination was already in memory, then it worked.
This is totally weird. I cannot explain it. The GameMode block in the first try was identical to the SEFF update block in the third try, yet the latter one worked, while the first caused a system freeze.