As of Schick version 4.4 you can add peers by entering their address. This is how it's done:
Say, you have two Macs, one (Mac A) wants to add another Mac (Mac B) to his list.
- First, set a custom port on Mac B…
- Open Preferences, and enable and set a custom port
- Then, set on Mac A…
- Choose "Add by adress…" or hit ⌥⇧⌘N