In case you have already purchased the DP-170 port (first short version) and would like to use the 12-40mm lens with this port, you can have an extension made with a larger inner diameter so it can be used with the wider 12-40 lens...
As I have studied CNC Software Programming and know how to use milling and lathe machines, I went to a machining shop I know the owner of and have it made within 3-4 hours. The next process I need to do is getting it anodised which I will do as soon as I am back to the UK, right now traveling across Europe...