What does sitting for the PE have to do with anything here?
Small drywall cracks are perfectly normal in new construction as the building materials dry out or acclimate to the humidity in the house. Usually a one-time fix.
The tile cracking could just as well be a shoddy job.
In the 12...
I do have to interject something here.
There is a lot of talk on this forum about "you need an engineer not a builder...". I can understand where it comes from as this is an Engineering Tips website.
However, you cannot discount the advice of a good builder in a situation like this. Keep in...
Does anyone know of a reference for designing a moment connection of two HSS beams using end plates?
Basically a flange connection as you'd see in pipe spools but using square HSS.
If it turns out that the 6x6's are the problem you could temporarily support the floor joists and remove the 6x6's. Them on your block piers, remove the top course of block
and repalce it with a 4" termite block and then install double 2x10 or 2x12 girders.