Trying the Completion tracking options in a course I found a problem (maybe two) with "Course prerequisites". If select in this option a course how have the prerequisite the course that I'm try to configure, a student never can finish this two courses becouse one is prerequisite to other.

Well, when try fixit deselecting the prerequisites in this courses I cant do it, becouse havent any course to select in this options and is impossible deselect this option (allmost I dont know how).