The app will load under DESIGN->UTILITIES->ADD-INS.
To start the game, click the play button. You can also pause and reset the game by clicking the corresponding buttons.
Further options are described in the information/help file.
After you leave the game you can process the bodies manually if you selected the "keep bodies" option.

Controls:
You can move the falling pieces to the left/right by using the left/right Arrow key.
You can drop a piece by pressing the Shift key.
You can rotate a piece by pressing the Up Arrow key.

Install:

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.

Uninstall:

You can unload the add-in without uninstalling it by clicking the "Stop" button when the add-in is selected in the list box on the "Add-Ins" tab of the "Scripts and Add-Ins" dialog.

Unchecking "Run on Startup" causes the add-in not to be loaded in future sessions of Fusion 360.

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, you can uninstall it from 'Control Panel/Programs and Features' (Windows 7/8.1/10/11), just as you would uninstall any other application from your system.

When running the add-in in debug mode there might occur some errors in displaying the voxels. Some voxels are still shown even if the bodies are deleted already. However when running the add-in normally no errors appeared during multiple tests.