It is bug squashing week at WSAPI central! I had to release yet another bugfix release today, to fix the bug introduced by the previous bugfix. In my eagerness to get the memory from unused states back as soon as possible I ended up killing perfectly good states, which would eventually leave the whole system unresponsive.
Either download news versions of the WSAPI packages from LuaRocks or download the updated WSAPI installer or the updated offline installer if you want to install without a net connection. I have deleted the installers and tarballs for the buggy 1.3 releases.