Is there an online PGN editor for Blank Chess? Blank Chess is a variant where the board starts empty and the first two moves are placing the Kings on your side of the board. You can then either place a piece or move a piece in subsequent turns.

I recorded a game I played with my son in the same notation one would use for CrazyHouse, and would like to record it in a PGN (or BPGN) format to show it to friends.

Does anyone know where I can find such an editor online, or failing that, one that I can download to my Mac?
Caissa's PGN Editor claims to be what you want.