Toxtree sometimes freezes when using Java 7 update 9. We are not aware of such problems with Java 6, so the workaround is to use Java 6, until we announce a solution.
Might be related to JDK 7 change of the sort() method and a related CDK bug as discussed in
http://sourceforge.net/mailarchive/forum.php?thread_name=CAE5qDd3mnPc7vgmwE11zq5W6fV-SOHrZm9ZjZTnANDoEST%2Bcjw%40mail.gmail.com&forum_name=cdk-user
Fixed in SVN trunk since rev 1547. Tested successfully with JDK build 1.7.0_09-b05 . Will be included in 2.5.8 and higher releases.
Swing UI was freezing due to incorrectly updating the UI in the background thread. The old custom Swing worker from < JRE 1.5 was removed and the one from javax.swing package is now used.
Fixed in version 2.6.0 http://toxtree.sourceforge.net/download.html#Toxtree_2.6.0