the attached zip file contains updated copies of the Configuration/Shared/Spry/DesignTime/DataSetsManager.js and EditingUtils.js files that should correct the problem.
Locate the users configuration folder, for details see this page:
http://www.webassist.com/tutorials/Common-installation-issues
then browse to Configuration/Shared/Spry/DesignTime/ and paste the attached files in that directory, then clear the browsers cache file from the configuration folder.