Customized custom keyboard shortcut

Hi - I am trying to add a keyboard shortcut in LO Writer to use the increase/decrease indent functinoality. I can do that fine by using the Tools : Customize : keyboard and assign to a pre-defined shortcut slot, eg Cmd-8 and Cmd-9

However I’d rather assign the shortcut to Cmd-[ and Cmd-], or something else not listed in the slots.

Is there a way to do this yet? I can’t see that this has been asked before, but if so, a link would suffice…

I’m using LO on Mac OS X 10.7


try macro.