Suggestion from participant: Show directory structure more

A participant suggested adding a slide/image that shows what all of the relevant files created at each step are, and where they are located. They found the moving among folders confusing, and would have appreciated a visual overview that might run parallel to the "train map" showing which files were made at each stage, what they contained, and where they live.

Review the training module steps, the existing "train map," and the folders learners move among. Identify the relevant files created at each stage and their locations; done means providing a visual overview that shows those files, where they live, and what they contain.

Written by the indexing model from the issue text.