problem with button assignment

[mlevin77]

I'm using Settings -> Personal -> Buttons to try to assign actions to hardware buttons. The attached screengrab is what I see. Can someone tell me

1) what the heck is that 3rd line with no button listed?
2) when I assign, I get a list of programs and some special actions (from the droplist at the bottom) but is there a way to assign it to a shortcut or a Mortscript of my own? It doesn't appear on the dropdown list.
3) how do I actually get it to map the available hardware buttons, when tapped or held down? For most, I can't seem to tell the utility - when I hit the button (say, the "Today" button) it does what it does (goes to Today screen) as opposed to tell the settings that that's the button I have in mind. On my XV6700 I had an app that let me bind several states of each button. Any ideas?

thanks!

Mike