I agree have your local MINI dealer pull any service records for you. I know there are a few class actions on the N14 out there, I believe the time chain tensioner is not settled yet. there is one for the HPFP that is settled, to reimburse cost.
***Warning personal opinion*** Seafoam or any cleaner are good preventative maintenance, but if the build up is already there manual removal (i.e. walnut blasting or some other form) is the only way to truly remove the buildup.
I run seafoam twice a year, but I also had to do the walnut blast at like 80k, but I bought it around the same mileage as you did 45k. It just depends who while the previous owner maintained it (ask dealer to pull ALL service records).
Now a myth about seafoam the white smoke is NOT carbon buildup burning off!!! It is a petroleum based product, that when burned produces white smoke, that white smoke coming out of the beater in front of you isn't burning carbon deposits. Its just burning oil.
Hope this helps and feel free to ignore the small soap box.:ridinghorse: