Quite simply. Unzip the MAKO dock onto your desktop. Now there should be a folder with a bunch of images in it. Take that folder, and paste it here:
Reload OD, and it should be selectable in your list of docks
Upon downloading the dock, I noticed it had 4 folders. Paste all 4 into that directory, and they are all selectable from the list. I assume you have OD Plus... not sure if there are any non-tab versions.
Hope this helps you.