If you want to launch all BlueZone sessions at the same time, you have to turn off the Launch Pad feature.

The Launch Pad feature is designed primarily for those Customers who have complex multiple host environments, and they want to provide their End Users with an organized presentation of those hosts.

If your requirements are very basic, and you don't need to use the Launch Page, then turn off the Launch Page feature.

Launch Mode features are controlled via the Page Properties tab.