EDITING question

Hi, I just upgraded to X2 and I would NOT go back to X1!!! ; thanks to Cakewalk team, you make a difference. Now, I am trying to get a hand on the new editing manners, especially in the in-lane new way to work. There is something I don't understand. When I try selecting a time zone, clicking left on mouse, in order to use shelf tool to lower a certain part of volume, the selected zone DOES NOT remain selected. Its grayer zone that is suppose to show me the znoe i just selected does not stay gray when i unclick left mouse button. AND when I go to use shelf tool, the ICON shelf tool appears in the top znoe of the automation lane, BUT DISAPPEAR as soon as I left click mouse in order to lower the volume. Is there someone understanding my problem somewhere and having a solution? Please! thanks!