Returned to the fray today and yes there was a short (speck of solder touching both live and ground on a pot - bridge volume). So re-did the soldering of several spots as wires are very fine and easily breakable whilst installing the electrics into the body. Success at last. Sounding pretty good so will see how long it lasts this time around. Cheers for the reply Simon.
It's amazing how small a loose blob of solder or how fine a whisker of wire can be to cause silence or other issues. Despite the joint between the coil connections on a 4-wire humbucker being factory heat-shrinked, I had a pickup that would only work as a single coil because a very fine, basically invisible whicker was poking out the end and touching the cavity shielding (and so always splitting the coil). Easy to fix, but still a pain.
I am quite pleased with the sound quality; given it's acoustic/electric means it's a big rounded sound. Only problem I've had is tuning - the Bigsby means that I have to tune it every time I play which I suppose is not a big deal. My mistake with the original colour (Dingotone Butterscotch) was that I only ordered one set of stains, not realising the size of the guitar surface was as big as it turned out to be. But I'm happier with the green. Wiring is a challenge but hey that's what kit-building is all about! Good luck with your build.