When you roll the ball between 2 meshes that are at the same height the ball sometimes bounces off the collision edges. This makes the game more or less unplayable since you randomly lose control because you can't move in the air. You could fix this by lowering the max contacts offset substantially in ue4's physics settings....

Is there a way I can contact the creator directly about technical issues with Sphoxie that might just be issues with my personal setup, rather than the game?

it is still too short.. would it be more levels? or workshop to create level??