Bittersweet update tonight in the most literal sense of the word I can think of.
First, the good news. Tonight, special delivery via BC (thanks once again Chin

you can't imagine how happy I am with this new toy!!):
Unfortunately that's not all that's happened today. At the 11th hour, ie.:
This:
So with water not 2 inches from the overflow point.. I decided before it starting spilling into the sump that it would be a good idea to pull the sump out and silicone around the stand to contain floods to the tank room in the eventuality water gets onto the floor. Ya know it's gonna happen sooner or later. The bonus for this would be that it would be easier to clean the sump outside of the stand.
So, siliconed the stand around the edges, cleaned the sump, maneuvered it back into place, and .... pop. The arrows and the dotted line show the extent of it, it goes from the top, down 2/3 of the way into the first baffle space, does a 90 degree bend and then back into the first chamber down to the bottom. Stellar maneuvering there of the sump Tony.
It had been a few weeks since I had a good swearing session over a tank build development ... trust me the streak is over. And the RO/DI shut off. In the words of Kevin Kline in "A Fish Called Wanda" - "I'm just a little *disappointed*."
Thought about patching it but .. I dunno. My old 75g had a sump that I cracked too, and I lived with a patch. It looked so ghetto. I'm going to price out an entire panel tomorrow and a patch piece and decide from there. I may just elect to replace the whole thing. Other than the silicone on the seams and baffles it would be a straightforward thing to do, it just means I have to wait though some more before I can test my return pump plumbing. ARGH!