Well, I was wrong. It wasn't anything simple.Thius from DreamHost support
This issue was caused by
nfs locking on our server. Basically, the ZenCart installer was trying to
check for free disk space in your account, and one of our internal file
servers that the tailspin uses was checking the disk space through was
having a bit of trouble that caused it to hang when asked for the amount
of free space. Everything is now rebooted and cleared up, and the ZenCart
installer appears to be working (I was able to get past the License step).