Ruth - I do something similar. I teach health professionals how to teach and train other health professionals, students, and patients. However, many of them come back and tell me they actually use all the information they learn in this course on the job. Its interesting - we have been writing to professional bodies in the USA and Australia etc. That's very important.
Simplicity is the key to online instruction.
Students don't want the bells and whistles with courses, only video games. They also want to be able to find the discussion, to find their test scores, to find responses to their essays. Another important concept is that the faculty become involved in the development, design, and construction of web pages. The more control you have over your course, the easier it is to manage. It's somewhat scarey when you first start designing pages.