A Staircases puzzle

A Staircases puzzle, like the one below, is a Latin square where a cell–connecting path indicates identity between connected cells' contents.
The above problem is my first attempt at getting published on Puzzle Picnic, under the moniker Term. Puzzle Picnic is a great idea: a community database of grid–based logic puzzles, which provides applets for both constructing and solving online. In short, it is a great place to present puzzles of standard types and reasonable size. Under the fold, I'll be discussing the experience, both of using the site and of creating the problem.
Being unfamiliar with Puzzle Picnic's authoring software, I opted for a puzzle type that I thought would be easy to create, easy to keep around in text form, and easy to test for stupidity on my part through computer–applied brute force. All of these turned out to be good ideas at one point or another. I did run into a few user interface problems (partly relating to my poor eyesight), as well as a documented bug, but admins were swift and obliging in their response.

When I first settled on the choice of puzzle type, I thought something like: Identities? That's like the lamest addition to a Latin square ever! Inferior to sudoku, inferior to futoshiki, inferior to pretty much every other known expansion. What can one do with that? The answer, it turns out, is a couple of newish logic patterns for you to visually recognise. I tried to make a puzzle whose challenge lies there, rather than focusing on X-wings, or other techniques generic to Latin squares.