Swarm Agent not distributing correctly

I have managed to get two PC’s hooked up to swarm agent, and when going to build, both successfully pass the inital stages where it collects photons, but once that is complete, only the main PC (which the build is being run off in the first place) continues with building lighting, whereas the second PC appears to have stopped. What could be the possible reasons for this?

http://i.imgur.com/PLlYPeS.png

Why would you need two pc’s running swarm anyways?

If your level takes 40 minutes to build you can effectively distribute the load, its very powerful.

As far as i could test it, that’s because of intense swapping on your slave node (add some RAM to it or use smaller importance volume in UE)