Running Mendix and Logging In
At the top your will see a button that says "Run Locally" next to a button that says "View". The dropdown arrows in those buttons give different options for running and viewing. Each version of the instance will have a bar at the top of the app, indicating what kind of instance is running. The Stop button on the middle will shut down the instance.
There is no "hot-reload", when you make changes, you must press the Run button again to apply changes, the page will then be refreshed if it was already open.
Run Locally: Running locally is ideal for 90% of your project. With some more modules, you can test CAS, email sending, role-assigning and pretty much everything else. Red bar at the top.
Run (with a cloud next to it): Running an instance on Mendix's free cloud service. From my experience, it isn't super necessary, the least used instance. However, before you move up to more important instances, make sure it works on this instance.
Licenced Node: Mendix's paid cloud service. Set this up when your app is getting closer to completion. Refer to the Licensed Node Setup page for this. Necessary for final testing and sending to Production.
When you click "View" after you are running instance, you will open your app. You should be automatically taken to a login screen, if not, click Sign In on the top right. Log in with
This is the default username and password for the administrator on the local instance. Not necessary to be changed, since you should be the only person logging in to a local version of the app. Later, this will be changed to use CAS instead of this login anyway.