Premise:
Make QuickBuild able to define steps which execute a script from disk as a build step without clever use of groovy shell

Reasoning:
Being able to version control groovy scripts for the build system independently gives QuickBuild a built in way for scripts to be versioned beyond versioning the configuration alone.

Implementation:
This should be a Step which allows you to specify a script location and working directory like any other similar step type like Shell commands.

Related thread:
https://support.pmease.com/PMEase/QuickBuild/topics/2125/storing-groovy-scripts-in-version-control