I first saw this feature a few months ago from an enquiry of a client, our client's requirement was the ios must support rmonv2 as well as EEM, my colleague and i did not have any idea what was eem... so I searched the net and read about it, however still I seemed to know the feature but never tried to use it.
Last month I encountered an IOS bug issue whereby the reinsertion of cable caused connected route no installed in routing table, toor had suggested to use eem. Nevertheless the bug was resolved after my client upgraded the ios version.
Here's a demo of my configuration which worked, the objective is to backup configuration to an external tftp daemon every day at certain time, time should be synced from a better stratum server to make it work correctly.
There are predefined variables in the IOS that start with "_", there's a variable for email server as well, during an event of a problem admin can be notified via email sent by the EEM, meanwhile can do workaround using EEM.