Clash Grouper is very easy to use. 

1. Select if you want to create the groups using each clash's ITEM 1 or ITEM 2 as a reference.

2. Select all the CLASH TEST you need to be grouped.

3. Select the grouping criteria: ElementId, Guid, Hash Code, Level, Grid Location, Status, Approval, Assignment, Created Time, or Source Model.

4. Click OK and wait some seconds.

5. The magic is done.

The installer that ran when you downloaded this app/plug-in from Autodesk App Store will start installing the app/plug-in. OR, simply double-click the downloaded installer to install the app/plugin. You may need to restart the Autodesk product to activate the app/plug-in. To uninstall this plug-in, exit the Autodesk product if you are currently running it, simply rerun the installer, and select the "Uninstall" button. OR, click Control Panel > Programs > Programs and Features (Windows 7/8.1/10/11) and uninstall as you would any other application from your system.

Some users behind a Firewall or proxy may have problems activating the add-in. Please follow the instruction on the link to solve proxy problems.

https://forums.autodesk.com/autodesk/attachments/autodesk/78/504135