Offizieller Kommentar
It is an option for all flights but you can select No to say that you don't want to use it.
The simulator is in the top left corner of the Options Menu:
https://support.dronesmadeeasy.com/hc/en-us/articles/211468103-In-App-Simulator
Save edits to a mission can not be done. You have to create a new file. We have things tied together all over the place and editing an already saved mission would break some of that.