Hi, Can.
The Progress Bar shows activities that can be viewed by the user. It shows the same activities as can be seen on the course page. If an activity is hidden, by one of various means, it will not appear in course page or the Progress Bar. If you want to use activity restrictions but still allow students to see what is coming, make sure that the activity is still visible but not accessible in the course and the Progress Bar should follow that.
The Progress Bar should not be affected by the course format.