You just need to choose what kind of element you want to renumber between:

1. Room, Room Name, Area, Area Name, Grids, Doors, Structural Columns, Structural Framing, Mechanical Equipment, Electrical Equipment, Windows, Any Component Family Instance, Space, Viewport, Link Names...
2. You can choose the target Parameter by Name, add prefix or suffix and set zero paddings.
3. Remember to use escape to exit tool.

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.

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.

To reset ElementRenumbering:

Delete file: C:\Users\USERNAME\Documents\JOTools\ElementRenumbering2017\Configuration.xml
Where USERNAME is your Windows username and ElementRenumbering2017 correspond to Autodesk® Revit® 2017 version.
Try this if ElementRenumbering is not working.

To move ElementRenumbering to default Revit add-in tab:

You just have to create, in the same folder as DLL, an empty text archive called add-ins.txt.
If you are using Revit 2016 just create C:\ProgramData\Autodesk\ApplicationPlugins\ElementRenumbering.bundle\Contents\2016\add-ins.txt