The UI dots are memory dots so that if you change the way the programs looks as far as size of document, whether the library is open and to what folder, or if params/properties are open. Say you change the size of the document window and you want to remember the size, you resize the window, and then click on a memory dot to save the new size to memory. To clear the dot, just hold down the ALT button and click on the dot to clear it. Hope this helps. you also have Camera dots and Pose dots