Thank you for your post.
When you mention opening the settings menu, do you mean the gear icon in the upper right corner of the page? This menu typically would allow you to see the session ID details as well as view the app in a previous version. If this is blank, could you clear your browser cache and see if this helps? It may also be a good step to test in a different browser as well to see if it displays differently this way.
For the app exiting, could you share some more details around the scenario? I’d like to make sure I understand the specific details for this question so I can be sure to get you an answer for this question.
In terms of the having access to data sources, users will get access to the data source through the connection they use for the app. If they are accessing the data source through their user account, they wouldn’t be able to make any changes to the data that they cant already make through their normal user account.
I hope this helps!