Since the update last week, Ad Hoc Analysis is broken and unusable by our organization.  All existing calculated metrics have errors and we have been told that all of our metrics need to be manually rebuilt, which we have thousands of.  The ability to copy and edit calculated metrics has been remove...

I completely agree.  This is an absolute necessity!  It is too easy to lose all of your work and is extremely frustrating.  Adding a prompt would alleviate any mistaken clicks on the x.