A few Desktop and update questions

[Artim]

LL does have a built-in compositor, you just have to turn it on.  Menu Settings Settings Manager Window Manager Tweaks click on Compositor tab and check "Enable Display Compositing."

LXDE is cool, but to use it you have to log out of the computer, and log back in choosing LXDE as your new "Session."  While you can mix a few compatible apps between desktop environments (Xfce, which is LL's default desktop) and others, from KDE and Gnome to LXDE and even Enlightenment.  But each desktop is a separate session.