I have to confess to taking almost 2 YEARS to find the trip meter button - when I caught my finger on it by accident !
On a 4/4 Sport (2009),you have to press the button briefly to change from total mileage to trip mileage, then press it upwards and hold for 4 or 5 seconds to zero it. I find that sometimes it jumps back to total mileage without zeroing but trying a second time usually works!
There's also an instrument light dimmer - it only took me 3 months to find that one (on rhs under dash near drivers door. I found that this "dial" moved clockwise and anti-clockwise but seemed to actually do nothing. (I always fiddled with it during daylight hours !). Only when I had my first service did I mention it, to be told it dimmed the instruments : I twiddled the knob (

Gentlemen, please ) that evening and the instruments went dim, then bright again!!!
Cheers