ERROR: CSGPlane::clipWindingToPlaneFront: error in polygon clipper
CSG is a system which uses boolean operators to combine shapes in order to create complex surfaces, CSGPlane being one of those surfaces. It seems that the engine tried to extrapolate a potentionally corrupted (as Greek2me said) model to the front of another surface.
I'll try looking through your add-ons list in a moment to see what possibly could contain the model.