For security and quality control reasons, only registered users of the game server can submit a bug report. Do this by logging into your "Web Deck" account, via the button on the top of the page, and accessing the Bug Reporting feature. For all other users, you can see a comprehensive list of the bugs reported, by version, below. These lists can also be found in the downloads themselves, in a bugs.xml file.

ALPHA
0.0.28
  No bugs on file. Try harder, people!