I am new in Linux, but heavily experimenting Redhat 7. That's what made me decide to run Desktop Switching Tool in the default Gnome menu and change the window manager to TWM.
I logged X completely off to the command line to enable it processing changes. Then I used 'startx' again, wondering what would have happened

.
But instead of presenting me a new appearance the whole thing hangs now where once the Gnome window has been showed up. My screen keeps being grey with the small cross in the middle of it. I can't reach Gnome any more.
Can I turn it back to Gnome? Any help is welcome. Thanks in advance!