custom D-bot bottom corner

This is a corner piece for the D-bot bottom corner vertices. It uses the parameterized corner piece here: http://www.thingiverse.com/thing:1543523

The original had 70mm of rail covered in each direction. I used I think 40mm instead. The original parameterized corner piece was monstrously large, so I trimmed it down to something more reasonable. I also made it so in each direction two screws were used instead of one in each rail slot.

The attached photos show this corner piece printed out i