"clickable area too small"

I created a couple buttons on the lower left part of the UI, next to the "belt" buttons. I have them pretty low, almost lined up with the bottom of those belt icons; but the area to click on the buttons is only at the VERY tip top of the ICON. 

How do you adjust how large of an area the button is clickable?

Well in this case there is not much to do about, I cant change how rust UI works but what can be done is, you can place another transparent button over the original button with same command and no text with just slightly bigger size. 

Changed Status from Pending to Not a Bug