New Mini Owner! Hello!

Hello! Bought a new (to me) 2012 Mini Clubman a few months ago. Got about 100k miles on it now. Thankful not to have encountered any major issues yet. Also, I do really like this car. It's for my GF, and I'm tempted to get another one with a manual for myself.

I don't know much about these cars, and I already looked up some of the known issues, mainly with the transmission. This is a standard model, so no supercharged engine, which I've heard is more prone to failure. The check engine light is on. It seems to be the exhaust cam sensor, and the thermostat. It's intermittent, so I'm not too concerned, and I haven't noticed any issues while driving, so I'll get to those eventually. The biggest thing is I just want to know if there's any quick and easy things that can be done to nip any potential transmission problems in the bud. Things that I can do myself, mind. It's the 6-speed auto trans.

Thank you!