I've created a collection in the Administrative Templates Manager and I've added policies to that collection. However, they are not showing up in the main window.

If your Admin Station is Windows 7, ensure you have .Net Framework 3.5 specifically installed on your management station. Later versions of .Net Framework are not compatible with Netwrix Endpoint Policy Manager (formerly PolicyPak) on Windows 7.

If your Admin Station is Windows 8 and later, ensure you have .Net Framework 4.0 or higher specifically installed on your management station.