If I launch Timing Analyzer standalone, and create IO groups (Analyze --> Against User Specified Paths --> by Defining Clock and IO Timing) with selecting one or more ports under the Port Name, then type a new group name and click on the button <create group>, Timing Analyzer crashes. This happens to all the device families.
The work around is to use the Timing Analyzer Plugin version of ISE. However, only several device families are supported in the Plugin. For those families that do not support the Plugin, this is scheduled to be fixed in the next major release of ISE.