OK. I have done everything you asked me to do. I have a fresh install in a subdirectory of http://www.spirit-edu.com of WPMU Dashboard, CoursePress Pro, and Marketplace.
I increased the the memory allocation in the wp-config.php to 1 gig, which is the max available, and I have only two websites on the serverthis one http://www.spirit-edu.com/learn and the one above, which means my server space is at 17% of its 60 gigs. It's a VPS linux server.
The above and Jetpack and Akismet are the only plugins installed in this install.
I put together a course, filled out the Paypal API, pricing everything that needs to be done.
1) The WPMU Dashboard doesn't show up in the backend, but shows as being installed and activated.
2) When logged out and you hover over "Courses" in the menu, there are no dropdowns (submenus) showing for "My Courses," Login, etc, like there were in the install I had done before.
3) When I do click on "Courses" I am taken to the course page, and it loads and I scroll to the bottom to click on "Details" it takes me to the full course description, but there is no button to "Enroll" or to Sign in.
4) I can go to "browse Products" in the right column (widgets area) and from there go to the cart and attempt to buy the product, but unless I previously have a user name and password, I can't login to pay for the course.
I have not a clue as to where to go from here, and although I can't give you backend access through the WPMU panel, I do have a username and password I can email you to check it all out.
The WPMU dash is installed on the http://www.spirit-edu.com site, but I kept them as separate installs.
Your assistance would be greatly appreciated, if I am to have a course starting in 2 weeks.