Hi, I've posted a similar bug report on kinggath's sim settlements page (on nexusmod), but subsequently I think I've mostly narrowed down to this addon pack. As of now, only the 'Modern' model will be completed if it's chosen for the plot, for the rest the scaffolding (and the construction audio) goes up as per normal but disappears after a while, and only the base remains.
I've tried changing building models using the Architect's T-Square; using the Immersion Breaker Breaker to refresh the plot; moving the plot then canceling action; and destroying the affected plots then replacing them with new ones, but none of them solved the issue (one settler was even doing the blowtorch animation on her plot).
I've tried changing building models using the Architect's T-Square; using the Immersion Breaker Breaker to refresh the plot; moving the plot then canceling action; and destroying the affected plots then replacing them with new ones, but none of them solved the issue (one settler was even doing the blowtorch animation on her plot).