Hi. I'm Alex Eulenberg, creator of the online Mac keyboard layout generator at http://wordherd.com/keyboards. This online tool was used to create the Mac Colemak downloadable keyboard.

This is to let the Colemak user community know that I have now made things easier for Mac users who want to adjust their Colemak keyboard layout: I have added an option to select "Colemak" as the base or "standard" keyboard layout. So now there is no need to paste the entire source (i.e. QWERTY->Colemak mapping) if you want to generate a Colemak-based keyboard. So for example if you wanted a Colemak keyboard with an option-S for smiley (Unicode character U+263A), you only need to check the "Colemak" option for the standard keyboard, and put one rule in the layout specification box:

Os $263A

This will give you a Colemak keyboard layout with the Smiley assigned to option-S (option-D on the physical QWERTY keyboard).

You can also just leave the layout box blank to create a standard Colemak layout with no "option-" keystrokes defined.

Enjoy!