IP address oddities.
 

I dont know if this is normal but I am seeing 192.x.x.x addresses that are not those of machines on my network. I don't know if this is just some configuration odditie on the other users end or what.

Depends on where (on which screen/table) do you see these addresses.

In the search and download candidates mostly. Occasionally I see one in the uploads table.

These IPs are from users on other private networks, obviously not there real external IP, they are usually firewalled.
But you could still be able to connect to them via PUSH if you are not firewalled too.
If you are firewalled and cant accept incomming connections and you dont like to try to connect to private IPs check the 'Host is behind firewalled' switch.
Also you can uncheck the 'Connected to LAN' switch if its not necessary for you to download/upload from machines on your private network.