I set this up last week with no issues following the instructions from this post, expect I changed from PAM to local and created new user from the web GUI:
http://lime-technology.com/forum/index.php?topic=43317.msg451171#msg451171
The connectivity test within the app doesn't work, it always fails for me too.
All sorted now, for some reason my router wasnt saving the port forward changes, did a firmware update. Changes saved. Connected straight away!