Number one - never plug a normal servo into the TinkerKit outputs as the power connections are different.
It is possible to use the "Display Header" and the TinkerKit outputs as "normal UNO" type connections, you just need the pin mappings.
I have them both at
http://21stdigitalhome.blogspot.com - one for the display header (see in December), one for the TinkerKit outputs. I have used both for connections beyond a display and beyond Tinkerkit to connect "normal UNO" type objects.
It can be done. Enjoy, Mike