zarf You don't need to connect anything to the Neutral output, but the switch does require a neutral connection in order to power the breaker.

zarf No. It's a buck converter, not a buck-boost, so with a 12V supply you'll be limited to output voltages below 12V. Even if you had zero volt drop through the RD6018W, you'd be limited to 18A x 12V = 216W. You'll only ever get 1080W output at 60V x 18A, and for that you're going to need a power source that's providing over 60V in.

zarf It's just the M2 expansion board, the USB link and a replacement bottom part of the case to accommodate the M2 expansion. ie: It's the bits illustrated in the first picture in the listing.