HI Alex, the issue with the dents is usually caused by the mast extension - ie when the sail sinks and the base/ring on the extension pushes into the board - this gets much worse if you remain sitting on the board when the rig sinks - not sure if this is what happened on your board, but will pass on your feedback - but remember this is a racing board, so it's built to be as lightweight as possible, most reinforcements are in the box/inserts and other areas which come under stress.