I have a vanilla football MP mission which was working fine back in 2015 on steam workshop.
It requires you to push a box (which is the football) into the opponents goal.
However in 2016, the friction between the host and client is not synced, so that only host can push the football.
The football has the this code to make it lighter:

football setMass[1,0]

The host is the person who createVehicled the football.
When the host pushes the ball, he can push it at full speed. This is because the ball is so light it has almost no friction.
But when the client pushes the ball, it's still light but there's so much friction he can barely nudge it, . This didn't happen in 2015.