I have created a template and saved it. So far all good.

Then I edit it and the changes are kept in memory but not saved to disk and when I have to force a restart it starts up with the initial version of the template.

The current work around is to open the file in a text editor and edit the template in JENKINS_HOME.

OS: Windows Server 2008 Service pack 1 - it runs as a service
jenkins: 1.570
Email Extension Plugin: 2.38.1
Email Extension Template Plugin: 0.2

And let me know if you need any additional information (This is the first time i have left the web interface so I have most likely missed to attach some log files but have not been able to locate any that seems to contain information regarding the plugin)