@ seanfilidis - will continue discussion within the github ticket -> https://github.com/jesseward/plex-lastfm-scrobbler/issues/16.
@b4th - i added some additional debug information, could you download and install a new build at https://github.com/jesseward/plex-lastfm-scrobbler/archive/master.zip and reinstall. Start it up and pass along the log output as you have done here. Please also dump your config in http://pastebin.com/ .
thanks for the bug reports ;-)