Part of this exercise is developing reports based on Invoice Total. Invoice Total is Optimized during this exercise too. Everything went fine, but the Invoice Totals are 0 in the report. I created a test report of my own that is just Case ID and Invoice Total with no summaries or filters and the Invoice Totals in that report are 0. I know I created test cases with Invoice amounts and even added a couple more after running into this issue.
I'm guessing the issue is with the Optimization, but I don't know enough about using the platform to investigate.