OAM PS3 11.1.2.3.0 Pre-Authentication Rules

We currently have OAM PS3 up and running, and we are trying to apply a few pre-authentication rules to some of our policies.  I have two main questions regarding the rules.

1. What is the syntax for doing a "false" check within the rules (for particular methods)?

     Example:  Condition:  location.isIPinRange('192.35.50.180','192.35.50.188')

     Result if True: Switch Scheme

The above rule is fine if you know the range of IP addresses... for instance, internal network addresses.  But what if I wanted to apply a scheme switch when an external IP address is accessing the resource?  How do I say "NOT location.isIPinRange('192.35.50.180','192.35.50.188')"?  Is it just checking for " > 0", " == 1", etc?