Several people have noticed that when they calibrate their robot as the instructions show, the robot's max height seems too high. You'll know the robot's max height is calibrated wrong because it will look wobbly, floppy, or just sorta strange when transitioning from point to point. If you notice this problem, you can put the brain into calibration mode, then remove your delta's paddles (the grey arms) and put them back on at a slightly lower pitched angle. When you put the delta in up/down mode, it should match the image in step 19 of the instructions http://robot-army.com/deltaInstructionsREV_C.pdf.
We'll shoot a short video to demonstrate incorrect and correct calibration and post it in this thread soon!