How do I open my grid set at start up in The Grid 2?

When The Grid 2 starts it shows Grid Explorer so that you can select a grid set; you may prefer to configure The Grid 2 so that it will skip Grid Explorer and display your grid set right away. To do this, browse to File (from the menu at the top) – Preferences, and select the option Start the default user immediately. 

You can also select which user is your default user at this point via the Default user drop-down menu.

Next time you start The Grid 2, you will start inside your grid set instead of Grid Explorer. If you want to access Grid Explorer, you can select File – Grid Explorer from the menu bar at the top of The Grid 2.