I only have been roleplaying trough mass msn talks.
So i do not have much experience with trolls..
I do have together with a friend of mine set up our own forum based on Hetalia, when we were still in the whole hype of it.
For some reason, I have not encountered any people trying to godmod or anything weird on there, but that is maybe because it is mostly 1 on 1 with everyone kinda knowing each other..
Right now I stopped roleplaying for the most part, but we still run the site, as there are still people happily RP'ing on there.