When Mac gets up from the ground after filming Bozer's monster scene, the first ping pong ball he removes from his face is the one on his chin. A few moments later, as he walks past Jack, the ball is still on his chin, but the two that were on his cheeks are gone.
The location is supposed to be in Labuan, Malaysia but all the vehicles are left hand drive - Malaysia is a right hand drive market.
When Ralph gets shot they hide behind a plant holder which wobbles as MacGyver leans against it, showing that it's not concrete like it looks.