OK. Let’s talk about the worst Creation Kit bug yet. This bug is so serious that it will actually prevent many modders from releasing their Skyrim work until it’s been fixed, and I have also heard modders talking about quitting Skyrim modding overall. It’s really serious, and I can’t stress enough that Bethesda needs to fix it.
Obviously the NavMesh bug has been in the Elder Scrolls and Fallout series since 2007. Basically the bug makes player-created NavMesh disappear upon reloading created cells. The NavMesh is the area upon which NPC’s walk and move around, so removing that, makes all NPC’s stand still and just… well… just stand still. It can also make NPC’s disappear altogether and Companions following the player start behaving badly. For scripted scenes with quests and events this is nothing short of disaster.
This bug doesn’t concern the Skyrim.esm, which is why Bethesda’s vanilla game works OK. It only concerns user-created .esp-files. Converting your .esp into an .esm doesn’t seem to help either though (according to reports).
I have encountered it in my own Primby Town mod several times and it’s not fun to watch. The only solution is to quit the game and restart if you want the town NPC’s to behave properly again. Some modders have been accused of breaking peoples’ games just because of this, but as for Primby Town, it doesn’t break the game entirely since Primby doesn’t touch the vanilla areas much, but rather adds new features into a little travelled part of the land. Nor do I do any quests at this point. In my case, it just looks stupid.
This bug is on my priority list. Bethesda needs to fix this. Take a look at this video for a better description of the bug. Here’s a link to the official forum thread on it as well. Bethesda has reportedly stated on some Twitter that they’re investigating it, but it’s been there since 2007, so what’s up?