As with much of my documentation, this is based on the great write up at Bricktable. I just added a few pictures and some more verbiage.

Plug your arduino in, make sure it is recognized by Windows (this can be done on a windows machine, or as in my case in a Parallels VM). Once you know the hardware is being seen, fire up the Mprog you downloaded.

Click the Magnify Glass icon, to search for the arduino:

A sucessfull find will give you the feedback like the this (see bottom left text area):

Now click menu “Tools”, option “Read and Parse”, it will look like this:

Check the “Use Fixed Serial Number” check box:

Put in a serial with format of “a40h-xxx” where xxx is a number, most start with a40h-001, then do a40h-002, etc. But in theory you could put any 3 digit number in here:

Save it:

Once you’ve saved, click the lightning bolt, that flashes your arduino, close down this app, open up arduinomeserial and you’re arduino driven monome should appear in the drop down with the number you just gave it.