Keyboard navigation

Is there some way to do proper window and program management using a keyboard? I have tried to use the keyboard shortcuts menu but am unable to close an application using the defined shortcut.

I am also unable to close or open a running application from the launcher (the preview windows). But launching an icon works using enter.

It is possible to use the UI using the keyboard by alt-tab cycling between windows but it is not optimal. The only real missing feature is closing an application. I have not found a workaround except killing process from terminal.