Fixed it. Thanks guys. I habitually use the Community Skybox Pack (CSP) v2.1 for the sheer variety of skies available. Turns out I used the wrong
CSP_v2_1.hak. Seems that there are actually two haks with identical file names on that project page. One with all the files and one with just the 2da… You can guess which one I was pulling my hair out over. I couldn’t understand why all my skies were plain grey. Don’t know when I acquired the 2da one but it now no longer resides anywhere on my PC.
Here’s a couple of in-game views from the village in the module after the fix -
Still got to do “set dressing” (i.e. placeables, etc.) and populate with the necessary NPCs to bring it to life.