Cancel partly matched bets

[laymore]

I need to have an option to have the remaining bet cancelled that is not fully matched by the first taker. I don't mean fill or kill as I want to do bookmaking and as soon as I get matched I would need to have the remaining amount cancelled as there is a good chance price will move through me if there is a second bet wanting my price especially inplay.
How do I do this please??

[laymore]

how can i do this?

[Jace1]

try hitting X when you have hotkeys enabled.