Sample Text Files
Generating sample text files for the puzzle generator is a time consuming affair.
A quick starting point are the sample text files included in every collection of WPG puzzles. Follow the steps here:
Sign in to the WPG so that the console comes up:

Click on the Access Now button of the Word Puzzles Generator tab.
That should take you to the WPG Puzzles Home.

Click on the Access Now for any of the puzzles. In this case, I am clicking on Scrambles.

Click on the Create a Scramble option and enter a collection name.
Save it and then click on the View option of the tab of the newly created collection.
The new scramble puzzle editor page will have a link to download a sample of the file.

Download the file, edit it and play around with the puzzle creation process.