So I've created a building in Ivarstead, with an NPC who has a set routine (go to the inn, wander around, etc), and I'm trying to figure out exactly how exterior navmeshes work since Beth hasn't posted a tutorial for it yet. I've tried altering the exterior navmesh by hand but I'm only using the knowledge I have of interior cave navmeshes. In any case, I may have altered too much of the exterior navmesh and I was wondering how to revert it back to the default Skyrim.esm navmesh without having to redo the whole mod. At the same time, I've run into the navmesh bug with ESPs where loading 2 different cells and then returning to the modified cell bugs the navmesh and all the NPCs within that cell. So basically I'm just looking for advice on how to handle exterior navmeshes, whether that means using auto-generation again for that cell or doing it all by hand.

In the CK, Data > select your file > Details, then find the form(s) you wish to remove overrides to and hit the delete key marking them as "Ignored". Upon saving/reloading, the "Ignored" forms will be removed from the plugin.

Also, before editing a Skyrim.ESM NavMesh, give it an EditorID via the Cell View window > Edit > ID and plug in its FormID (will always be unique). This will reduce the likelihood of you inadvertently replacing Skyrim.ESM NAVMs with isolated forms native to your plugin.

When I 'ignore' all the NAVMs in the Details section the CK crashes upon loading the mod. And one of the NAVMs is marked with a 'D', so I'm not sure if that is conflicting or what.

In any case, I decided to try out the ESM fix for the navmesh bug by ESMifying the ESP using WryeBash. The first thing I noticed upon loading in though was that the objects and terrain that I had initially edited for the mod have been undone, almost like the Skyrim.esm is being loaded afterwards. I deleted a rock here, adjusted landscape level here, etc, and now when I load in those changes are undone. My building is still there, but now it looks out of place due to the terrain it's on reverting to default.

Well that's helpful to know.

What do you do though if the navmesh you need to edit doesn't yet exist? Or if what you're doing results in the original navmesh needing to get broken into two (fences etc)?

Find NAVI and "Ignore" it too. Upon saving, NAVI will be rebuilt.Stitch in time saves nine From what I've seen, it's only the 00 NAVMs that are at risk of being deleted and replaced. NAVMs native to your plugins should be safe w/o EditorIDs.

Wouldn't any changes to the navmesh be saved to the ESP itself and thus not directly modify the ESM? Or is all navmesh tied to the ESM? That seems very troublesome to me.

JustinOther, isn't there some way for me to just auto-generate the navmesh for that cell again and save it? Or would that somehow mess up the default navmesh that's in place with Skyrim.esm? I'm just hoping that I can use one of the auto-generation features to completely wipe and redo any chances I made to a cell, and then just fix them by hand; but I'm not sure which generation method to use as Bethesda hasn't posted a tutorial for exterior navmeshes yet.