Well, I was trying to host my office DM today. It was on Building 6 (default save), so I added a velocity pad in the elevator shafts.
When the first person joined all of the sudden my blockland froze. Then it got to normal. Later, while I was playing the DM, I crashed. Frustrated, I restarted the server. Then, I crashed again while making something no-collision with autowrench.
Usually when I host, I crash a lot, and on certain servers I'll be loading then it just closes randomly. Attached is my console.log.