After receiving several reports of my mod causing crashes on save, I was able to reproduce it in one of my savegames. However, I have not been able to determine the cause. Any general advice for troubleshooting this kind of problem?

My mod replaces refs of crucified NPCs with new ones that have low-level processing. On activation, depending on player choice and a roll, their object script gives them a travel package, and at the end of that package they get a sandbox package.

Even though I am doing this with other NPCs with no apparent issues, one specific group of NPCs (the crucified powder gangers in Nipton) are causing CTDs in some savegames after being freed. The crashes start to happen after the player leaves the cell that the actor ref is in, and will occur regardless of whether their travel package has been completed. The scripts are slightly different, but even after changing them to make them as similar as possible, the issue persists. I don't see any substantial difference between these NPCs or their refs and the ones that work.

I have removed the download from the Nexus until I get this sorted out, but if anyone wants to be a hero and take a look, the file is available http://www.4shared.com/file/GsCdSjju/Decrucifixion.html.

Huh, on further testing, running masterupdate on my plugins appears to fix the crashing issues... anyone know what would cause this?

I know replacing vanilla wasteland objects improperly (i.e. just deleting them then placing your objects in) causes this kind of issue. NEVER delete vanilla objects. Either move them out of the way, or set them to initally disabled. Deleting them tells the game that the record number is available, so your mod uses it for the next placed object. But you then have your mod telling the game "This number is my record, for this objects." but also its telling the game "This (same) record is the vanilla object, now set to initally disabled." So there are two records with the same ID, which the game engine doesnt like, causing it to crash alot when you save near it, or fast travel, and a few other things. I'm thinking masterupdate and those things you did fixed it by assigning a new record number to your new object, removing the conflict.

Setting the vanilla refs to disabled seems to do the trick. Thank you :foodndrink:

I had been under the impression that using replace in the GECK just pointed the reference at a different base object. I even did an undelete and disable in fnvedit to be sure, and it didn't undelete any references... huh.

It does, but under your new mod index. So technically you are deleting the original ref.

Like said, in future just set them to disabled and move them underground or something

Ah, I see... that makes sense. Thank you.