I was having the same problems - say yes to the 'temporary' pop up - then the page is reloaded and the template change is reversed and any other unsaved changes are gone.
I suspected the MySQL v php server time problem (though it has never caused problems before) the thing was where do I find the MySQL server time zone? (this on shared hosting - limited options!)
Here are two ways:
1 - I have access to my data base via phpmyadmin:- after logging into the manager and doing something I went to my shared hosting control panel, opened phpadmin and looked at the Structure of the modx_session table - there is a time of the 'Last update' there in my case it was the same as my local time equivalent to UTC -5
2 - Click on 'Create New Document'. Select the Settings tab, Click on Published On and click on "Today" - a date will appear - go over a box and click, a time will display this time seems to come from the MySQL server (at least it did not match my php server time)
Finding the 'php time' is easy - you write a snippet and stick it on a page
$now = date("F j, Y, g:i a");
return $now; or perhaps easier: in the Revo manager Under the Reports tab select System Info - you can view the phpinfo and look for the time setting which I think will be the same as the "Server Time:" just below the link to "View" phpinfo
So if they don't agree go to "System - System Settings" type time into the search box - then set the Default Time Zone - I used UTC -5 since my MySQL server was 5 hours behind my 'php time'
Worked for me ( on revo 2.2.0 pl2 )
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