The port charts are a PDF download, they can be found by going to Nauticam.com. On the home page go to knowledge base at the upper right, then go to the port chart PDF link and download the PDF. Scroll down to the M43 lens chart then to the 12mm lens. You will see that Nauticam recommends one of the 4.33 inch ports or the 3.5 inch port combined with the 20mm port extension. The port extension also works with the Panasonic 45mm macro port for use with the Olympus 60mm macro lens.
These charts can also be found within the NauticanUSA.com site but just go to Nautican.com and follow the links.
The 17mm pancake is the F/2.8 lens the 17mm f/1.8 is the larger lens and may not work with the same results Alex got because if does not focus as close.
Ah, my mistake for using the Nauticam USA web page which clearly isn't up to date! They have a very basic m4/3 port chart only.
The m4/3 port chart direct link is: http://www.nauticam..../catalog_18.PDF
Also it seems like my GH3 kit lens 12-35 mm F2.8 is supported with the same dome as the 7-14 mm (6" wide angle port). Still I think the 12 mm F2.0 is a nice addition.
Basically three ports will cover my five underwater lenses (65 mm macro port for the Olympus 60 mm, 4.33" dome for the 8 mm fisheye and 12 mm, and 6 inch dome for the 7-14 mm and 12-35 mm).