I am also new to testing Qlik Sense Implementation. I did not get much details online, but somehow figure out few ways to test it. I will try to answer your queries in below manner:
- Make sure All Visualizations are intact. Nothing is broken.
- What have been change - Is it a Visualization, Dimension, Variable, Some kind of Formula, Data Model or Sheet level change.
- If it is a Data Model Change - you might want to compare the outcome with data Base where you would be preparing SQL query as par the filter.
- QlikSense is a associative implementation - so make sure each graph/visualization gets updated with the filter that you've added.
- When the App is ready it would be published(and I believe it would be a Master Copy) - so you can cross verify it with Prod.
- You can test QVD file only with your application.
- Common things: while analyzing the result - make sure that there is no Cartesian Product in data model - which can produce an incorrect output, Verify Section Access (Different User will have different Security access)
I am still learning new things in testing Qlik application. I hope my reply might have helped you a bit. Let me know if you have received any better solution for your queries - This will help me too.