Hi,
TargetPro in this case is delicate because of the way to destroys gameobjects, in a network situation you destroy object within the context of the network, and so targetpro needs some code editing to allow for this.
If you already over comed this problem, then targetpro is fine, use it locally, and instead of synchroinize targetpro, synchronize the health of the player itself. Remove TargetPro from the equation, and simply let it run on the client as a tool.
BUT, be careful with your network setup, cause if you are using non authoritative servers, then you CAN'T run targetpro or any physics based systems relyably without a huge initial work, because each simulation will be different on each client, target pro ( actually, the way your missile is going to travel and be guided) will be different and so you'll have problem with state synchronization.
Bye,
Jean