Hmm - tried an older version (http://btsync.s3-website-us-east-1.amazonaws.com/) And now getting connection closed issues (similar to http://forum.bittorrent.com/topic/24886-sync-over-relay-server-blocked-downloading-file-file-due-connection-closed/) Doesn't seem to want to work on my Pi Shame, had it working a few months back Oh, before I switched I increased the number of open files but once it hit 20k I thought it was getting rather silly.