Can I sue the co-signer of my car for financial contr. if he refuses to sign nec doents to register it?

In 2008 I needed to buy a car for college and work, at 19 I was unable to get approved solely based on my income and limited credit so my boyfriend co-signed. Now we are seperated and he lives in TX (where we bought car) and I live in OH. The car is currently not registered because, according to the state of OH both signers need to be present to transfer the title and register. The other signer refuses to sign a temp POA form issued by the OH DMV (so that he doesnt have to be present). The cosigner also of course will not come in person. I have already had to pay a $300 ticket for the vehicle being unregistered because I need it to get to work, and I have made every payment towards the car(eliminating 1/2 the loan debt). I cannot get the car refi'd because of my debt to income,despite my 730 FICO. Can small claims court make my ex sign the nec forms to register the vehicle or can I sue him for all my past financial contributions if he refuses to cooperate with me in making the vehicle legal? Even if I drove across country and paid all the fees to reregister the expired car in TX, this would still not help me in the fact that it would not be registerd in the state that I reside and work in, and I make all the payments. I know the obvious solution would be to just let the car get repossessed but I cant take that on my credit and really need reliable transportation to and from work. Can anyone let me know if I have enough legal standing to bring this to court or is the contract with the dealer and financer going to leave me helpless?