Theresa,
I think if you do a SUPPRESS inside the condition (with no CONTINUE or SEND anywhere else) the Xlate will finish but no message will be generated.
Otherwise, you always could put everything else under the condition on the path where you want to build the message and then the message will only get populated if the condition is false (still placing a SUPPRESS in the true Path.
However, it sounds like you really are doing message filtering and for my money that is best done in Tcl prior to the Xlate (I like doing it as a pre-xlate in the route definition.
Jim Kosloskey
email: jim.kosloskey@jim-kosloskey.com 30+ years Cloverleaf, 61 years IT – old fart.