Just adding to this thread and the issue being a big one that needs to be hotfixed.

Can confirm this issue, which appears to be specific to this building on the first floor. The slightly raised main floor does not have object collision with most items during placement.

I found some players today that repeatedly were killing our group of 4 in official server 5306, including right after we spawn. It started off with them killing us through walls and clipping into our base, speed movement across a field, etc. They appeared to be griefing us. They appeared to be from somewhere in Asia.