""Hi Nudibrano, I have the Zen port already, but putting a decent Macro lens behind a dome seems a bit odd.?""
Why? Underwater, a well designed dome should always be better quality-wise than a flat port but you lose the FOV by about 30% with a flat so if you are trying best magnification you generally prefer a flat port (but you may be able to focus closer so...). However the 60mm has already a large focal length (even too large if you think that I have the 45mm and sometimes I wish i had less for some small fish...). I have used my zen with the 45mm to simplify my switching of ports and frankly I would have not bought the 45mm except for focus delays in the large space between the port and the lens. Instead you should have a proper distance for the longer 60mm lens and I hear the 60mm is much faster to autofocus (reason I am considering buying it).
With the zen I could just switch for the 9-18 WA lens and for the 45mm macro without changing ports. After seeing the results I never used again the flat kit port from Olympus and used the zen for the 9-18, 14-42, 45mm lenses.