Yes it is the DI (Down imaging) that won't work with the US-2. Here is what will work using the MKR-US2-9 cable.
Lowrance
Cuda 168, Cuda 168EX, Cuda 128, Cuda 240 S/GPS, Cuda 240i S/GPS, Cuda 242, Cuda 250, Cuda 300,
Cuda 350, FishElite 320, FishElite 480, FishElite 500C, FishElite 520C, FishElite 640, FishElite 642C,
FishMark 320, FishMark 480, FishMark 500C, FishMark 640C, SeaFinder 240DF, SeaFinder 245DS,
SeaFinder 250DF, SeaFinder 320DF, SeaFinder 480DF, SeaFinder 500CD, SeaFinder 640C, SeaFinder
642C, SeaCharter 320DF, SeaCharter 480DF, SeaCharter 500CDF, FishEasy 2*, FishEasy 245DS,
FishEasy 250DS, FishEasy 320C, FishEasy 350C
X-4, X-4 Pro, X-47, X-47EX, X-50DS, X-67C, X-86DS, X-96, M-52i, M-56, M-56i, M-68C, M-
68i, Elite-4, Elite-4X, Elite-5, Elite-5X, Mark-4, Mark-5X, Mark-5X PRO
If you look at the stickies you will see you can make it a neat job of running the cable down the shaft. And FYI, you can remove the cable going to the US-2 by unplugging it under the cover of the head. MK assured me this will not affect your warranty. I don't know about the networking
Fair Winds and Following Seas
Bill H. PTC USN Ret
Chesapeake, Va