I’m re-texturing existing models anyway. 
dont mean to necro this post but i just happen to find this, and had a question about the nwn_crunch. is this added somewhere on the vault or forums here that can be easily located? this is something that is quite useful, and still works!
As mentioned earlier in the thread:
https://neverwintervault.org/project/nwn1/other/tool/nwn-crunch
I normally open the dds with nwexplorer and export them in tga.