I have absolutly no lag at all, and under normality the mesh I got has brilliant collision, due to it was made by Hamilton. The bridge has no gaps, and it is not flat. x3 The "Bridge" Is a log.
EDIT: I restarted my computer and FH in my brilliant rage of anger, and by some miracle, it solved it. (I also deleted something but I forgot what it was e.e) Lock please, but keep it up so people who have this problem know what to do. c;