FBC 1.4 is designed to have no conflicts PHP wise as I've rewrote all the classes. Aside from this I can't guarantee any previous release won't conflict. No Conflict mode just checks to see if the classes had already been defined, if they are then it won't include the API. If only half the classes are defined then FBC will break, which for some reason other devs keep loading half the API. At any rate this is all fixed with 1.4.