After install and run Nuvola Player, it does not end the session opened.
After the installation, it left a bug in Unity. When I put the mouse over the bar in some application, sometimes does not appear the name of the program right.
My video card
Intel® G33 x86/MMX/SSE2 gave me no problems on Ubuntu 11.10 and Ubuntu 12.04 before. But now Ubuntu sometimes has some flaws, such as Unity starts flashing.
I uninstalled Nuvola but it didn't work. Also reinstalled the system and nothing. I leave this video that maybe can help.