You can easily change your design in Q-Cal between the designs you already have. 

1. When you're on the frontpage of Q-Cal, click on Views.

2. Click on Meeting Room Displays.

3. Find the screen that you want to change the design on and click on the small gears.

4. A new window will open. Click on Design and choose the design you want.

 

5. Click on Save & Close.

Note - It can take up to 5 minutes before it is updated on the display.