here are a couple of ther times it's been reported. perhaps you'll see a commonality.
http://www.lotustalk.com/forums/f101/hardtop-hairline-cracks-53414/
http://www.lotustalk.com/forums/f92/my-paint-cracked-37881/
searched:
crack* hard* *top
http://www.lotustalk.com/forums/f101/hardtop-hairline-cracks-53414/
http://www.lotustalk.com/forums/f92/my-paint-cracked-37881/
searched:
crack* hard* *top