I'm trying to use AddScriptPackage to add one of three Packages (Follow, Wander, Wander) to an NPC, but it is not working.

After some exploration, I've confirmed that the Script IS working, but something is messing up the packages. Specifically, I swapped out these packages for one I made earlier, and it worked perfectly-- then I closed Oblivion, looked at the Package, and re-loaded, and now it is not....

I'm certain it's the Packages for three reasons:
- I've done this before without an issue
- I'm using a Script I've used before which works perfectly
- The other Package worked perfectly until I looked at it in the CS.

So far I've tried re-writing the packages, downloading a new copy of the CS and a new copy of OBSE, but without look-- anyone have any clues?

Are you using a clean save game?

Things 'are' saved in your save game that can override any mod changes you make at a later date.

Yep, I am using a cleaned save.

I've had another go today, and it randomly works now-- which is good of course , but still a little conerning: why would it suddenly stop like that? And then re-start? I'm thinking a conflict, but the only other Mods I'm running right now are the official DLCs, KotN and SI, so I can't see them affecting EVERY NPC the same way...

My guess? You might have been using a dirty save game unknowingly. Happens all the time.