How to Direct MarketPress to CoursePress after Payment, Exam Page, Unit setting

Hi,
Please help me with the following:

1. After paying the course fee at MP (marked paid already), the student is not directed to the purchased course despite using the "order status" page. How to make the correct redirect?

2. in Unit Settings, what is "Force unit completion refresh"? If he clicks DONE on each unit, will the unit be refreshed to "unread"?

3. Mandatory assessments or test page: Where can I find the tab to create exam or assessment page? It's the same (add page) in the unit settings?

Best regards,

Vi