Scripted Extensions - How to get them to work?

[snrl tryout]

I read through the docs:

https://sites.google.com/site/snarlapp/developers/creating-addons/scripted-extensions-reference 

But can't get any of the examples working. The doc says "Each script extension must be in its own folder." but doesn't say *where* that folder should reside. I tried the 'extensions' folder of Snarl (in Program Files), but it isn't recognized. If I put a zero-byte file <folder-name>.extension next to the others, it is recognized by Snarl, but only as an invalid extension. I guess that functionality is for binary extensions...

I tried Snarl 3.1 as well as 4.0.beta.7.

Any help?

Note: I want to make an extension, with an event handler to the Snarl pulse (via ext_Pulse())  with a simple App Preference page (need to store a string value).

Thanks for any help.