If it worked with the D180 it will work the same with SkyView. There is no functional difference in the way a SkyView talks to a transponder and the way our D10 and D100 products did.
You do not need the converter with a 327. Run the TX wire of any of the 5 serial ports to the RX pin on the 327, then configure the output format on that pin to Icarus.
Yes, hook up the transponder to both displays, but turn one output on and leave the second output off. If you lose the first display, just go into the serial setup and turn on the second output (you can do this in flight, it takes only a few button pushes and knob turns). It works, I have done it in testing.
Here is the HS-34 compatibility page - another page should be created for SkyView compatibility, or another column for SkyView should be added for links to system-specific wiring.
You do not need the converter with a 327. Run the TX wire of any of the 5 serial ports to the RX pin on the 327, then configure the output format on that pin to Icarus.
The 320 is an older transponder design and doesn't accept serial in. Only the 327, 328, and 330 do. You'll need out converter if you want to use a Dynon product as the encoder.
I have the Becker 4401-1-175 transponder and it has RS422 output, will this communicate with the RS232 on my Dynon Skyview for altitude data or do I need RS232 to graycode converter?
RS422 is a no-go on that model. The next model up (the 6401) describes that you can also get an RS232 signal using half of the RS422 wires, but I'm not sure we've heard of people doing that. It looks like the gray code converter will probably be needed.