I just discovered this thread and really like the idea of expanding the list of possible anims for NPCs. We at Silgrad Tower just recently added SI compatibility primarily to increase the number of possible anims. With that, I do a couple of observations/questions:
- When adding an idle anim, order matters much as it does for an INFO record. Each IDLE record contains a DATA record which consists of the form IDs of the parent anim (usually just a group, not a real anim) and the previous sibling anim. Thus adding an IDLE except at the start of a group will result in another being altered as well and deleting an IDLE in the middle of a group requires that the following IDLE be changed to replace the newly deleted previous anim. The version of Gecko currently in beta does merge such IDLEs w/o error, but remember not to "overclean" your mods of seemingly extraneous altered anims; there's a reason that they are there.

- Another area we've ventured into is anim objects; it's always nicer if your Dunmer mattock doesn't magically transform into an Imperial hoe during the anim. Has anyone else added new idle objects?
- If a mod like ST were to decide and get permission for using another mod like AiC, how would that work in terms of both the CS and in not exploding the setup when a player either does or doesn't have AiC installed?

Thanks,
Steve
First of all, I'm just going to point to http://www.gamesas.com/bgsforums/index.php?showtopic=999587&hl=.
Now that this is out of the way...
1. You can remove the idles altered. The CS will complain at the first startup, but this sets the custom idle to be working while being clean.
2. Adding new idle objects is very easy, they're just another kind of objects to define (and combine with a new idle anim entry, using the same kf file). However it wasn't done yet, because likely no one ever bothered to do so

.
3. AiC and AiM use Vanilla kf files. If you set them up to be used by AI packages, you don't need these mods at all. Instead you have several options, the imho best I have outlined in a previous post here. Or use the thingy linked above

. As for unique new idle anims, simply change their kf file names and include them as new anims (including them also in the download). The method used for the player is by far not the best when used for NPC AI packages, so there's no need for mod deisolation here, neither for mod merging.