Thunder, Any chance you can look more into performance issues in the future or have tweaking advice. I can tell you not that its healthy but creating a couple max size MFFS can lag the server a lot but hmm wonder if there is other ways. I remember a bukkit plugin ages ago and I was pretty sure it was threaded but also sending packet to the client of blocks that were actually not there but showed up there to the client aand of course prevent the user from getting there. The performance was amazing I think because your actually placing a block in each spot and one forcefield could be many 1000's of blocks.
Idk just randomly spitting out ideas.