Using libraries with embedded AppleScript

I am trying to get the 'Run AppleScript' action to work but I'm running into a number of problems.
First, the embedded editor refuses to compile any 'use' statement (e.g. 'use scripting additions' or 'use script "MyLibrary"'). It gives the error message 'Expected “end” but found “use”.'
Second (and presumably relatedly), I can't get it to run any AppleScript handler. For example, this:
`script "myLibrary"'s test()`
It works without a problem in every other app I've tried but not in Hazel. Any help would be appreciated!
First, the embedded editor refuses to compile any 'use' statement (e.g. 'use scripting additions' or 'use script "MyLibrary"'). It gives the error message 'Expected “end” but found “use”.'
Second (and presumably relatedly), I can't get it to run any AppleScript handler. For example, this:
`script "myLibrary"'s test()`
It works without a problem in every other app I've tried but not in Hazel. Any help would be appreciated!