Thank you Mike,
I sanded and coated once... Looks much better already! BTW, for the sake of any future builders the Rustoleum professional flat black has limestone in the formula and I think might be the culprit in the cracking finish.
Cheers!

: Sand the hull well if the coating is cracked. You'll likely get
: cracks in the same areas of stress on the skin after a while. If
: the initial coating is well soaked into the fabric, it shouldn't
: leak even if the outer layers are cracked.

: Mike Savage
: South West Cork