So far the worker thread for building the navmesh works wonderfull i have seen no impact on gamestudio except for creation of the debugmesh which is not threaded... Have a working build status function which gets called from the thread with its result(it calls a script function).. The build thread handles the whole mesh instead of a single thread per tile (could perhaps do a thread per tile in case of the tiledmesh but not going to now) I am going to try and handle pathfing and agents on threads aswell which should help out with performance since gamestudio would not feel the algorithms impact ..