Hi. I recently bought and assembled the 10 inch kit. Ryan Bates currently has two images available on his website which are compiled for Raspberry Pi 2. One of them comes with Raspbian and is preconfigured for the GPIO module. The other is a more recent bare-bones Retro Pie installation with no OS and no input config. I downloaded the one with Raspbian preconfigured.
Overall it works great but I’m having a few issues with the MAME emulation. That’s a topic for another thread though. Cheers and I hope you got it figured out.