Follow Xenon's comment I got more concerned and actually phoned up the manufacturer. I was very please to get a response. Apparently the join along the wall is bad but the gelcoat is thick enough:
Hi,
I'm after a second opinion a new GRP bay roof we've had installed. We live in a 1938 semi which had the original lead on the front bay and previously had a plug hole for water to drain out of into the gutter.
Because of the original design the roof had no natural pitch for water to...