Limit the number of Instructors listed on front end

Hello, I don´t know if this is possible: We have a course with 21 Intructors each doing one unit. Now in order to show that they have a course on all intructor page I have to add all of them via coauthor to the course setup page. And to pay them a commision they also have to be added. Now we have a couple of problems: 1) Is it possible to show only the first 2-4 Instructors on the course page? It looks pretty shitty to have a long list like this: http://prntscr.com/f5qye0 2) As well as on the course list page. Can I only show a single Author/Instructor? (The first one) http://prntscr.com/f5qyky http://prntscr.com/f5qyri 3) As a coauthor he or she can´t modify a unit which is assigned to it, is this correct? Would be nice to accomplish that (at least it doesn´t show the edit course button in their dashboard) 4) I am not sure if its a bug but as a coauthor I am able to remove or add students. but once I go to next page on "members" tab it doesn´t seem to load the option to edit the student clicking on first page again same happens. I have to reload the members tab in order to load the edit options. (hope you understand, see attached screenshots) http://prntscr.com/f5qxwe <---with options http://prntscr.com/f5qy3t <--- no options 5) It seems like I can only add 21 coauthors but for this particular case I need 22! Is there a limit? Because it won´t let me add more. Thanks a lot for your answer