Irritation with the mpja breadboard I mentioned (touted?) in the previous post

Here's a photo of the T-connector:

The RED and BLUE notations are all mine. I had to buzz all the pins out to identify them (well, the left side row was guess-able, I suppose). No help from the supplier, though. This isn't the only mystery, though. The cabling is non-obvious, too.

The T-connector end of the ribbon is keyed -- but not the Pi end! Luckily, I tested the circuit all the way to the other end of the ribbon. Maybe you can make out the dim "2" (upside down) on the Pi end (meaning even-numbered pin side). I never would have guessed that cable twist.

"Other than that, how did you like the play, Mrs. Lincoln."