One extremely useful tool we use to help us manage the topic is Power Markers from Olympic. This is a fantastic add-on to Mind Manager that allows you to easily list selected markers in you map. We use it in the first instance to show us what has not yet been allocated, and what has been queried, along with the queries themselves.

Selecting any listed topic immediately jumps to that topic (expanding the branch is needed):

This is probably the easiest way we have ever looked through a set or requirements and checked off what has been done, remains to be done, or is queried. You can even copy and paste the displayed items (eg questions) to the clipboard to paste into an email!

We now select the status of the Design topics: