You have a good start, but your way off.
What you want to do is start all over.
In begginer mode, you can't delete or start over, so you will need to switch to expert mode.
In expert mode, you need to create a new show.
You will be prompted to save information. Don't save anything. Also you don't want to have any demo stuff. So creating a new show will remova all demo fixtures.
Now.. Create a new page with your coemar fixture, and when you get to this section, you need to say you have 8 fixtures as picture below.
No you should have 1 window of control that will control all 8 fixtures.
Let me know when you get this far.