The contact points are designed to be a bit loose. The drive usually tips forward under load and that is it. I would not expect this to cause the cracking issue. Rather the drive slipping forward out from under the knobs is the most likely cause. You can pad the spine as you did to limit the tip. You can coat the inside of the hull (under the forward contact point) with shoe or marine goo. That would be the best insurance against a leak there. We should have a kit for this soon.
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