Thanks for the info.
In another post I opined about the fun of buying a new trailer and the opportunity it gave a new owner to explore every nook and cranny - that's because if you don't right up front those little gremlins are going to pop up and make you do it anyway!
I've never bought a new trailer that didn't have a water connection leak somewhere so I just crawl into/under every location where there is going to be a fitting and check them. Invariably (every time) there will be a connection, or several, loose. At least the black tank flush valve on this one, unlike others, was installed correctly and did not leak! Good luck and I hope all the gremlins have presented themselves and it will now be clear sailing.