When you use alot of panels these spaces cannot be used to throw away items out of your inventory. Many players complain about this. Of course when you find a place that is not occupied by the MagicPanel you can throw away items but its still confusing for alot of people. Is this possible?

I would check all your docks and make sure you don't have anything oversized. You can change the color of them to debug their size. Outside of that I don't believe anything can be done about the UI blocking drops.