The trim cover seems to be useles to hide unused snap points on Arterium walls The other gripe I have is there are some corner pieces that could have been added in certain sets to make things uniform between joining one set to the next. The biggest gripe I have with the sets is the windows are foggy and dirty ffs. Mind you without Place Anywhere I don't think it would have been possible to what I did as the chambers are skewed in some joining areas and it would be close to impossible to have a continuous vault between all chambers due to not enough slope sizes for some sets. I have already filled the vault space to brim with building structures in one consecutive vault that all interconnect between all the areas right up to the other exits into the Commenwealth. There are no Half or Quarter size blocks pieces so you pretty much work with a 256x256x256 or 512xx512 x256 snap sizes. Learning curve of how thing snap from one set type to the next was a bit lame, but does have a nice finish after you work out the way to snap from one set to the next. The actual buildable structures were great to me. Shallow and cheap and not worth a pinch of salt. TBH the Vault-tec DLC to me was absolute crap for Quest Content.

Fallout 4 vault tec dlc start