Search this forum for 'oil in the air filter' (much has been written on engine breathing). This likely caused the check engine light. In short, you need to drive the car more often and get it fully warmed up most every drive. Re-locating the crankcase to oil tank breather hose also helps (search the forum). Ignore most of the advice to completely re-work your oil/breather system. The factory breather system is fine if you simply drive the car every few months and fully warm it up on most of your drives.
As for the check engine light, you can either check the fault codes and reset it with the free software available from S&S (again-search this forum), or disconnect the battery for a minute. Worst case you may have to remove and clean the oxygen sensors in the exhaust, but that is not likely.
