This variant can be interesting if you can hold the image of a cyclindrical board in your mind.

It would also be useful if you had a board you could rotate - ie move the files across a to h etc (so that the board runs b, c,... h, a and so on). The possible moves would then jump out at you. If you could make one of those you would have a clear advantage. Alas, I'm not good with building things.

In the openings, remember that, because there are no edges on the board, the center extends across the whole of the 4th and 5th rank, not just the d and e files. It follows from that, that there are no "flank" openings, even such fringe moves such as 1.a4 are no longer on the fringe, but are occupying the center (won't that be fun?).

One thing that annoys, and damages this variant as a game, is the sad fact that K+R vs K is only a draw. You can't force the King back, it can just keep going round and round the board.

By the way, castling doesn't move your King to the edge, it will still be in the middle (and anyway your rooks are already together and in the "center").