I had a cc3d in my flip FPV and I could turn the FC 90 degrees to easily connect the USB. But on my qav400 the spacers are right at the center and block access. So I have been pulling out my battery to plug in the USB which is very frustrating in the field. I finally hacked together a solution using mounting hardware from a frankenquad tomb combined with my shapeways case. Cc3d now at 45 degrees. Curious what others are doing.
Here are some pics. Note I had to use some spacers under the case as the button head screw in front of the USB port was also blocking the port.
I mounted mine at a 90 degree angle and just left the spacer that would block the USB connection off if the frame. Doesn't seem to have weakened the clean frame much at all.