Document Setup has three parts, the most important part is in the third Tab, where the Script Includes are managed.
This panel manages the Scripts that are included in your HTML page, the scripts managed here are crucial to Lucid and the script you are creating. If the correct Scripts are not included in your HTML, your script will not work correctly (or at all).
For the simplest of Lucid Workflows, you will probably have 3 scripts included, jQuery, JQuery UI, and the Lucid Workflow Script your are working on. These scripts must be included in the correct order..
1) JQuery
2) JQuery UI
3) Your Lucid Script
If you have not included one of these Scripts, or have them in the wrong order, the Issues feature in Lucid will flag this.
The General Tab controls the basic settings in your Script.
The 'Testing Web Page' of the Script is simply the HTML file that your Script applies to. This page is the one that will be opened on the right side of the main Lucid window.