Silly little jobs it's easy to forget, but will cause you pain if you do - snipping off the sharp ends of Peco track pins under the baseboard.
The plywood the Tim Horn baseboard I've used for my OO Billy Bookcase layout isn't very thick. Certainly not thick enough to absorb and an entire track pin. Stab yourself and you could almost think Sundeala was a good idea!
A few minutes snipping off the sharp bits with some flush snips and the problem was solved. I grabbed each pin while cutting with some pliers and wore protective goggles, just to be on the safe side.