Allow TCP or UDP In/Out to Allow TCP or UDP In
Source Port is 6346 to Source Port is Any
Make Destination Port 6346 (with p2p programs the source ports can be anything but data comes in at the Destination port).
Under Appliation Rules make sure that the Shareaza rule is somewhere above the All Application rule; you can drag it there. That is needed because when it is under the All Application rule it will follow the rule set by the All Application rule no matter what rule you made.
Show us a screenshot of the Application Rules as well to see you moved it successfully.