Yo enigma!
Please check out Dropbox & if possible H2HH, as they will both make your life so much simpler.
By using DropBox, one simply drops the game file into the shared DB, then your opponent retrieves said file and plays his turn, rinse & repeat. No need to wait on e-mail transit.
By using H2HH & DB together, your life becomes even simpler as all you need do is open the H2HH display, to see the status of your game, it will tell you who's turn it is, if it's yours, simply start CMBN, the saved game will be sitting there waiting. Play your turn and your done, H2HH auto handles your completed file and adjusts the display to reflect it is your opponents turn. You will never have to handle a file when using H2HH.
ps...newer versions of H2HH also have a message feature that allows commo with your opponent between turns.