Open the project file in Monarch.
Click on the "Home" tab.
If you see the list of "Recent Projects", click on the right arrow (off to the right side of the recent files), and you should be presented with either the Model Information or Project Information screen. If it is the Model Information, click on the word "Project" all of the way to the right of Model Information
Once you have the project information screen up you can click on the report tab
and it will list the report locations:
Hope that helps.