Comments/Ratings for a Single Item

Charles, well hit. Truthfully, I never considered the question of pawn promotion when I finished this up for posting. Embarrassing to admit, but there it is. I kept going back to the game with the feeling that something was missing, but the taxi rules seemed solid, I had the combination and breakdown rules set, the dyads and triads had their possible moves trimmed down to what I thought worked best [the original had R+R movement options of 'hookrook' and planar rook, for example, but those moves were too powerful]. Good thing this is a non-competing entry, apparently.
My initial thoughts, way back when, were that there was no promotion, the pawns would have to be carried off the back row by a taxi or as part of a combination piece, or using the optional pawn moves I left in the rules, should the situation ever arise. This is clearly a weakness in a *chess* variant design. Following are promotion rules.
Promotion would occur on the opponent's 3-square back rank. 
To promote, a pawn must, by itself, move onto one of the 3 promotion squares. It may not promote if brought to a promotion square by taxi or as part of a combination piece.
A pawn may only promote to a rook, bishop, or knight. This is freely chosen, there are no restrictions on availability of pieces or any other such conditions.
I hope this is satisfactory.

Or is the phrase 'well struck'?

As far as the number of squares actually in the game, I feel a certain
amount of ambiguity is good for the soul. I was quite happy to see Doug
Chatham's ambiguous square count turn up in the contest. 

As for the possibility of allowing the 2 taxis, with or without passengers,
to end a move orthogonally adjacent to an edge board square, well, the
board was modelled after a [poor] map of Manhattan, which is surrounded by
water. In fact, when the 45 square contest never materialized, I considered
adding 3 7-square rows to the middle of the board, changing the one black
and one white taxi [remember Black and White Cabs?] to two Checker[ed]
cabs, usable by either side if empty and callable, and calling that variant
64 [not 66] square Manhattan Taxi Chess, since the board would more closely
resemble that poor map of Manhattan. This concept precluded me from even
thinking of your idea, Charles.

It is a perfectly viable optional rule, however, and does fit in well with
the 45 square theme. Thank you for pointing it out. Grin, shows how blind a
theme can make you in design.