I'm glad I could be of help. I have thought for a long time about moves on a triangular board, but have never formulated them into a game. I have thought of first creating a page detailing numerous types of triangular move possibilities, and from there creating my game, with the first page as a reference. However, judging by the work done on the chessvariants wiki, I'm out of a job :) It's already been done. I don't know if it's possible to create a pure FIDE translation, but I'm glad I'm helping, and hope you come to a point where you can settle on what you've got.
I can make one suggestion: instead of pawns promoting in the opponents' territories, perhaps the promotion zone should simply be located on the opposite edge. That avoids the 'impure' sideways move. I imagine that there would be plenty of interference from both players, making promotion just as difficult. Just a thought.
Oh yeah! One more idea, but it's just an idea. Every triangular chess variant I've seen sets up the armies in the corners. FIDE chess is not like this. It might be a tad cramped and require a larger board, but what if pieces were lined up on the edges of the board instead?
I can make one suggestion: instead of pawns promoting in the opponents' territories, perhaps the promotion zone should simply be located on the opposite edge. That avoids the 'impure' sideways move. I imagine that there would be plenty of interference from both players, making promotion just as difficult. Just a thought.
Oh yeah! One more idea, but it's just an idea. Every triangular chess variant I've seen sets up the armies in the corners. FIDE chess is not like this. It might be a tad cramped and require a larger board, but what if pieces were lined up on the edges of the board instead?