The Groupname in the VM reporting tab is the same as the call flow name in the CCC Reporter.
Only select Call Answered if the call do not have a next action, a Leave Mail action will have the option "Call Answered" set, otherwise you cannot run a lost calls report as all calls are answered by VM Pro.
This is how to use the different things:
Group Name: use it to group a number of actions together, a menu in a call flow must be grouped together so you can report on this specific menu.
Topic : give each menu option a name, example pressing one will transfer the call to the Sales group, name the topic "Sales", give each menu option a different name.
Annotation: used for additional information on the topic like "Transferred to the Sales group" which make reports more clear.
You can have more menus which routes call to the sales group, if you name the annotations the same then you can run a report on the annotations to see how many calls were send to the sales group from any menu.
I have never seen it NOT working so you must have done somehing wrong in the naming of the actions.