I always get "Remote disconnected"  with a peer that uses Transmission 2.12. I believe its an old version of that program. Can this be fixed?

Same here, by any chance it shows a russian flag? might be an anti p2p organization btw

For whatever reason it disconnected you. It will try to connect after a while. You can speed this by right click -> CONNECT
Or change your SETTINGS -> Behaviour "peers " double click -> start/stop
Then you can just double click clients.
I normally don't worry about those so much. I worry more about clients which appear to suck data as fast as possible from me (not a known or recognizable location/address which will pull multi-MBps from me) without showing any update, or any download to me (upload from them). They are considered swarm "cloggers". You can read up on who would want to pollute a swarm by making your upload count for nothing because they upload nothing in return.