To upload your CSV, go to Access Manager > Configuration and click the blue "Add" button.
On the Configuration page, you can also set the Item Name and the Display Name. The Item Name is what you will see in the platform when designing your app. The Display Name is what will be showed to the app user when using the app. Both are set to "Access Manager" by default.
You can also set the Session Timeout - this is how long until the app user will need to login again. By default, it is set to "No Expiration" - this means that once an app user logs in successfully, he will never need to login again. The Session Timeout is "built into" the app when you do a build - this means that if you build the app and install it on a phone, then change the Session Timeout, the app will still use the old Session Timeout.
Remember to click the green "Apply" button to save your changes!