A few rather annoying glitches, some common, some not so much. One of the most common: My arenas fail to submit, or are impossible to play/beat. Yes, I allowed everything. A lesser known one is where it blares a loud, obnoxious sound repeatedly.
Each jelly should be slightly different. For example the Kingdom Rush one could move faster but jump lower. And the bomber smiley for Facebook could fall faster. Yes that's a good thing. No jumping, having the enemy run past you, and fall so slowly that you land on the slime. Horizontal distance is the same, AKA it's not heavier, it just moves faster when going downwards.
 "Bubble Tanks Arenas"){kind=icon}
 "Jelly Escape"){kind=icon}
 "Desktop Tower Defense"){kind=icon}
 "Paladog"){kind=icon}
 "3 Slices 2"){kind=icon}