Problems with the exercises for the Appian developer course

First post. Thanks for your attention. I am working through the Appian developer course online, and I've run into problems with the exercises. I will write the code to mirror the solution, and the tests still fail. This happened for a few of the exercises. My most recent problem is not a failed test; I'm working on the exercise to accompany Expressions: Enhance Your Data. I'm trying to create an expression rule, and a Rule Inputs pane doesn't open. I'm not sure how to continue with the exercise. Has anyone else had this problem? Do I have an old version of the designer? Any advice would be appreciate. Thanks