Sorry to hear of you having that much trouble so soon fella, a bit of advice with these things, do not start with any throttle full stop, pull out the fast idle and press the starter and don't blip the throttle after starting from cold, these are the things that feck the sprag, good luck with fixing, it's the worst thing about the bikes, but a previous owner has probably being starting it the wrong way.
I have done over 55k miles on Mille's and never had a sprag problem, in fact little very trouble in those miles and the bike does get used properly, good maintenance is the key and good batteries with the correct starting procedure.