Now that you've gone through the process once it should be easier for you to use it on one of your own stories. Even though the StoryGuide is presented in a linear order, you CAN use much of it non-linearly by answering questions about your story that you know FIRST and going back to the topics you're not as sure about later.
The value of Dramatica is two-fold. The first is the process of going through storyforming, storytelling (illustrating), and storyweaving your story. During that process, you learn more about your story than you probably would otherwise.
The second benefit are the reports. If you've created scenes or chapters, the Treatment report collects them into a story treatment or step outline. The other reports are valuable in different ways. Some organize the material you entered which is useful as reference material for writing the finished work. Other reports make observations about your story. Like any set of tools, use the reports that work for you and ignore the rest. You'll find that you end up with favorites and hardly use some others.