A nice little program. But sometimes when I use the NPC files, the game crashes (I figured out it happens when the created .esp file is 20+ mb. the usual, working size which is about 100-300 kb). I still don't know how to fix this issue and what's causing it. My first guess was that it probably had something to do with mods, but later I figured out that it's nothing to do with mods.
Great program, it has worked well and easily, but have had an issue with certain NPC face textures. Sometimes the physical changes take place: new hair styles or scars, but the colour/tone will revert them to a plain, clay like Brown. Been looking around and seen a few posts here and there of people encountering similar problems with the construction kit.