Chuck,
Sorry I haven't had time to check in on the forums lately, and you may have already figured out the answer to this. The only thing I can think of that would cause the basic empty sub Main{} not to work is if the "Script Language" setting in the Run Script action was set to something other than Perl, and it would give that exact error if that was the case. I ran into this a lot when I was testing out different scripting languages with Kiwi and kept forgetting to change that setting. It's definitely a "Thwack" moment when you realize that's what the problem was.
And while I'm here, Kevin's problem (just speculation after testing, theory crafting and playing around with the scripting engine) is likely that Kiwi's implementation of Perl probably doesn't support the external API. This would explain why he can run the script from the command line but not from within Kiwi.He may have installed the API on that machine and it likely works with the normal Perl implementation, but I'm not certain how you would integrate that with Kiwi.