A. A GUI can be as stylish and smooth as you like it as long as it retains functionality. There GUI can be moved around the screen if I can see right, making it as non-intrusive as possible so I wouldnt call it obstructive to a defree.

B. The colour does need to be changed,

C. Circles to need to be changed

Overall there GUI is NOT bad, in fact i consider it very stylish and yet effective, yes it has its draw backs but nothing meriting the type of post you just gave above. So stop being so unapologetically negative for the sake of being negative and offer them critisism in a positive way, you effectively attacked the GUI's weak points while not commenting on what you liked.