This is an "on the hoof" project and, as you can see from the second image, the paint work is not the best anyway but it's frustrating when you do the work and the outcome is so poor.
I spoke to a rep. from the paint supplier and he thinks that the thinners in the paint might have "broken through" to the primer and/or the original fibreglass gel-coat, and that is what is likely to have caused the problem. I have used the same products on steel and not had any problems. The other thing that you can see, is that some areas of the paint look okay.
His suggestion was to use a better quality two pack primer and a two pack paint. Unfortunately, I don't have a compressor and the two pack primer is harder to get here in Ireland. I suspect that my only sensible course of actin is to sand down the whole surface and take it back to the local body shop and let them sort it out. They quoted me €150.00 which i suspect is a reasonable price for a reasonable job.