well...to change hotbar you have a couple squares that make up just one key...each square is a different size. then you need to resize the entire window, another square. Then the frame, then the background, the the two buttons that change pages, then the little number that shows what page you are on....
Most windows are like this, unfortunately
But hey give me a x2,x3,x4 or however big you want and a window name and ill do one for ya after i wake up....just to get ya started

Going to bed now....late over here
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