For an end user:
- within a change request, on the Relationships tab, select a CI and use the quick action 'Get related relationships', which will show changes.
For Reporting: use the join forms I mentioned above (CHG:Associations-CI etc.)
Unfortunately I don't have a system in front of me to give you more specific details, hope this helps.
If you are looking for the change records, then on the CI record go to "relationships" tab and change selection to "change" and you'll see attached change request. Note: I don't think this is available from the Atrium console, you'll need to select "manage CIs" from a console and find your CI to see this.
I think there maybe a report included in the system that actually shows all changes by CI, but I haven't looked at version 7.1 for awhile.