So....no guesses?
Might all be a moot point now...was working on it some more, putting everything back to its original setup (going to bring the whole system in to be assessed) and I think I might have made a mistake somewhere...atleast if the smell of burnt electronics is any indication. Got that dreaded burnt smell, it was faint but distinct. But can't locate the problem, double checked all the connections, re-fired it up and the same result as ever, once again, no change!
Starting to think I could drop this thing of the roof, into the pool then pull it out, drive over it with the truck and still fire it up and get the same result.