LED lighting for 840 enclosure

According to the assembly manual for the Stepcraft 840 enclosure, the control board is capable of powering an optional LED strip (either from the dedicated LED headers or the 12v power supply headers). Regardless of what i try, though, i cannot get any power out of those headers.
Has anyone had any luck hooking up LEDs to the enclosure control board?
If so, are there any settings that need to be changed in the software to enable them?