It just skips a single turn, or half a minute of game time.The game is turn based like a dungeon crawler.
And the bar at the bottom of the inventory window that can be changed by clicking on it?
It lets you assign hotkeys to usable items. Right click to assign, and left click to use. You can also use the number keys 1-5 to use them.
I'm referring to the gold bar circled in the pic. Clicking anywhere along it changes where the bright/dull devide is at.
That's the bulk/weight bar. The changing part is a bug.