It is not possible to create your own exercise

As a new online coach and someone who’s been using spreadsheets for years, I was really eager to test the app first for my own training session to get a feel for the “customer experience.” However, when entering my first workout, there were two exercises that weren’t in the database. When I try to add them, I’m taken to a screen with a loading icon. After that, though, nothing loads, and I can only go back without saving. Is this a bug, or am I doing something wrong?