Motorcycle title stolen, what to do?

[Odiel]

Hi there.
I was unlucky/stupid enough to get pickpocketed and I lost the registration document of the bike. When I bought the bike I got an email with photocopies of all the documents, but because there were so many documents I failed to notice that the most important one, the title, wasn't among the copies. Yes, I am an idiot. Since the bike is not originally in my name (power of attorney) I can't ask for a duplicate of the title. I'm trying to find the original owner to ask if he still has a copy lying around somewhere. Idle hope probably.

I went to the police to get a certificate with heaps of stamps that says they were stolen and that I am the current owner. Took about 15 hours in total. Makes you appreciate the efficiency back home. Should this be enough to cross borders?
I have other papers like old insurance slips with the name of the original owner to prove it legally is mine.

Pfff had some problems on this trip, but for every problem there is a solution, right.
Any advice?