This might work, it might not, but I think it's worth a try, or at least to have stated here for others:
There is a program included in the tools.git repository on review.swgemu.com that contains a program called WorldSpawnerTool. It's a large cumbersome program that needs the original .tre files and won't read any .tre's beyone 14.1 as it's written. BUT, It does has an openGL interface to show you the mesh.
Since the program is hard-coded to look for the original files, if you find something in the later .toc files, then just add it to data_other.tre and it "Should" work. I've not tried it but I don't see why it wouldn't work if the .iff files are in a recognizable format.
Most of the singing clan and Nightsister models are "Dressed" models, i.e. they're not neked, so you should be able to find the model you're looking for.
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On the server side what you were told is correct. Basically each NPC you see in game is generated from an object template created in the LUA files. bin/scripts/mobile/* Those objects are then spawned in screenplays or other scripts usually found in bin/scripts/screenplay OR bin/scripts/managers.
Each NPC template can be setup to use whatever weapon group you wish to give it, Can have custom names, or STF names if one exists, Can be setup to use conversation scripts if the NPC is interactive, Level, damage ranges, armor ratings, HAM values, etc... are all set in these files. The non-dressed models can be dressed with scripted outfits as well.
Now I don't have any idea how SOE did it, but it seems to me that a lot of npc templates got re-used/re-purposed as the game progressed. It wouldn't surprise me at all if the witch iff got re-purposed as a named NPC as the game matured. Add a new weapon, or maybe a new clothing item in a non-slotted spot and you're g2g using the exact same witch IFF that was used previously.
One other thing that's important to note is that because of this, there are MANY entries in the STF files that are either non-existent in the later stages of SWG's run, or that were never implemented altogether. The STF's are just string names for things, and can be filled with all sorts of trash. I have tons of non-used names and data in my custom STF's that I might get to some day (added all my old buddies as I wanted to make NPC's for them until I could get them to play again. *smile* but I've not actually done it yet).
anyway, I hope this helps a little. Just like 1 tangible item can be used to represent MANY different items in game, 1 NPC IFF can represent many different NPC's in the game.
-Duff
P.S. I don't know of anything that's actually hidden in the client. Most everything can be accessed / changed in the .tre files, even the UI elements. I've changed my galaxy map to include taanab, that's not a client hack but changing the .inc file and adding the data. I highly doubt that there's any hidden IFF or other data bits in the client that the game uses. Or if there are, SWGEMU doesn't use them as near as I can see.
