If the belt brush GUI is clicked, it also brings up the blueprint mirror/upgrade GUI. This causes a shift such that the belt brush GUI is in a different location and trying to click multiple times results in a misclick.
Consider moving the belt brush GUI to the same line as the BP mirror GUI and ensure the belt brush GUI stays to the left.
If the belt brush GUI is clicked, it also brings up the blueprint mirror/upgrade GUI. This causes a shift such that the belt brush GUI is in a different location and trying to click multiple times results in a misclick.
Consider moving the belt brush GUI to the same line as the BP mirror GUI and ensure the belt brush GUI stays to the left.