I recently got a replacement 4x4 center from cubesmith.com and a set of 4x4 tiles. i just de-stickered my cube, replaced the broken center, and retiled it. but for some reason, there is an inner axis that will not turn. I have it colored with white across from yellow, and along the (white green, yellow, blue) center axis it is stuck. it turns on the other axis (you could say the x and z axis turns fine, but y axis is jammed. i think that i may have spun a center wrong and it was causing a lock up on one of the y,w,g,b sides.