Can you only indent to 1 level or is there a way to allow further indents?
Add my vote
Yes, just go to the row you want to indent and indent (Ctrl+K or the button)
You can't indent any row more than one level below its parent, but it can be indented several levels deep.
I know it will go at least 16 levels. There may be a limit but it likely isn't anything you'll ever need to use.
Craig