Here I am with some answers!
FYI: this is for the courses that were sent out in January 2008. There may have been changes since then.
The format of most of the courses is very simple. There is a recommended reading list, and a list of objectives (questions). For some courses, the list of objectives is long and focused on details (History of Midwifery, Anatomy and Physiology) while for others there are fewer questions and they usually require slightly longer answers, perhaps mini-essays.
I found the courses somewhat frustrating. I have a college degree, and I was somewhat surprised by the unprofessional way many of the courses were written. Many, many times my preceptor and I would puzzle over questions that seemed illogical or poorly worded. In the very first course, History of Midwifery, I kept running into questions that were strange or didn't make sense, and I had trouble finding the answers in the books available to me. Finally, by chance, I found another one of the books on the list at a university library, and upon reading it, realized that all the questions for the course had been written with that book in mind. The wordings were the same, and the questions followed each other in the same order as in the book. I was therefore able to complete the course more easily, but I think if someone didn't have access to that book (which I think is out of print), they would have a lot of trouble finding the answers (I will try to look at my notes and see which book it was, because this would be very helpful to current students I imagine! Edited: See below). It seems like laziness that they would not bother to write questions that could be answered by various sources, and didn't depend on seeing the answer in one book. The one course I loved, Statistics, was written by Melissa Cheyney and was fabulous. It was more like a college level course, and she provided all the resources which made it easier.
In sum: yes, the courses are doable, but it takes a lot of perseverance to find the answers they want, and your preceptor should be willing to work with you if you don't always provide the answer they're looking for. My preceptor was shaking her head at a lot of the questions! I almost feel like I would have learned more by just reading a few books on each subject, but I'm a fast reader and can absorb information that way. YMMV.
I hope this helps! If anyone has more specific questions please let me know. I am going to go try to look up that book for Hx of Midwifery! Edit: Here is the info:
Wertz, Dorothy and Wertz, Richard. Lying-In: A History of Childbirth in America. New Haven, CT: Yale University Press, 1989
You might be able to find this book at a local library or university library. I used to just go and take notes on books at the university library since I couldn't check them out.
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I'm still dying to know what the classes are like, though. 
The school administrators were always very nice and easy to talk to. I hope you have a really great experience. I think it is all in picking good preceptors.
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