Aww good job this is a great deck for a beginner! Also I can tell U how to fix the rotating!
Click on any actor, then go to "movement"
Then, choose "dynamic motion"
Now click on the "add physics or controls" button.
Scroll down and find the "axis lock" option. Click on it to apply.
There will be 3 physics:
Moves horizontally
Move vertically
Rotates
Click on the square next to "rotates" to remove the ✓
And you're done! Now if u drag, it won't rotate anymore! :D
I hope my tutorial was helpful