FCP to FCP

I am unable to run the same application on two different macs when connected to the network.
I got this set of instructions from creative cow:

Open the Little Snitch configuration
Click the Green Plus to Create New Rule
Change Allow Connections to Deny Connections
Click the down arrow with the gear to select "Choose Application" and Select {app name }"
Leave Server/Port/Protocol set to Any
Click OK

will this work?
thanks