Hi there, mart44. If you're referring to returning to the Start Screen after desktop apps are closed, so far as I know there is no tweak to return to Start Screen after closing desktop apps. Pressing the Windows returns there or while holding down the Windows key, press the period key, press the down arrow key, then release the Windows key. That hides the Desktop app, but doesn't close it. It never fully closes. It hides it. You can also drag it down like any Modern/Metro app, but it will remain in the switcher then reopen it using the mouse to slide out the Switcher Bar in the upper left hot corner or using the Windows key/D key combo. Using the key combination to hide it rids it in the switcher. The Windows key/D key combo is the only way to reopen using that hiding method.
You can also hide the Desktop app with open Win32 Desktop apps on it using either hiding method as well. To drag it down you'll have to size them or minimize to the Taskbar to reach the top of the Desktop app, though. The Win32 apps will remain open to use again if need be.
Please feel free to ask any questions if I haven't explained that well. It can be confusing.