Glad you got it working.
I wish I knew of some way to avoid this sort of problem. Clearly calibre picking one of the several IP addresses available didn't work for you, but we have no way of knowing *which IP address* is the right one. Perhaps we (calibre) should refuse to show any IP addresses if the machine has more than one of them in order to avoid this confusion. Perhaps showing them all would be better, with a notation like "one of 10.1.1.1, 126.96.36.199, 192.168.12.10, or 188.8.131.52".
There is no good answer here. Sigh...