In Mavericks I could click on an open window and hold down the mouse button (or trackpad) and drag it anywhere I wanted on the desktop. And to access the Dock I just scrolled down to the bottom of an open page and dock applications icons would automatically appear. In El Capitan, none of this works. So I am forced to press the Escape key to minimize the current open window so that I can grab it's edge and drag it to move it. I must also press the Escape key to minimize the current open window so that I can see the Dock icons in order to open other programs. Infuriating and time wasting.