Not seeing option to create virtual devices

I’m following directions from here: https://support.smartthings.com/hc/en-us/articles/200901330-Writing-Your-First-SmartApp
I created an app (or borrowed code from one of the samples) but when trying to simulate it I don’t see the option to create virtual devices like shown on the screen shot in the document. How do I create a virtual device?

it looks like that last screen is dated, you’ll be given the option to select a virtual device when you start the simulator.

you’ll be given the option to select a virtual device when you start the simulator.

Hmmm, there’s no option to “start the simulator” either!
All I see is a button to “Set Location” and when I click that to select a pre-configured location then it takes me to the Preferences screen to pick the devices and there’s no way for me to create a new virtual device.

Ok, I’ve figured out what’s going on!
The documentation is the problem. There’s a lot of experimentation and “figuring out for yourself” that has to happen given the state of documentation.
Anyway, for the specific issue I had - there’s no way to create new virtual devies you just have to use the ones automatically created for you based on the code. Also, for some reason the virtual device will not let you change the state in the GUI until you reload the app (this is how it worked for a contact sensor).
Hope this helps someone.