Can you confirm that you added a map to a project? If the only context menu option that is available to you is the "Add to New Map" option that is disabled, then you either don't have a map in your project, or a map is present but not open. On the Insert tab on the ribbon, click New Map. This will add a new map to the project and open it. Then you can drag/drop a feature class to a map, or right-click it and click "Add to Current Map". The "Add to New Map" option is not working right now, so it will always be present but disabled at PreRelease.