I hope the empty world issue will be fixed some day. Anyways it works on 1.9.2. It throws tons of errors, but hey - it works.
Instance whole worlds.
Error upon loading: http://pastebin.com/8k1B5psj
Uses old (3.6.5 for 1.8) ProtocolLib
If world to be instanced is unload, get this error and teleport is unsuccessful: http://pastebin.com/0DkUJmZE
If world to be instanced is loaded, you get a completely blank world and fall into the void. Using creative, determined that this is not a loading speed issue, but rather the world stays empty.
As is, the plugin is unusable.