I have the same problem....
I dont know about you but the cron job does not work for this module correctly
I am busy rewriting the module for myself ..... with extra's like memo upload area for the students to view (with critea that they may only be able to view the memo after the assignment hand in date etc...). Individual updating per students mark's/feedback etc. Also a log tracker to view all the files that have been replaced by the teachers or students ( resubmitting ) with access to the old replaced files ( specially created for those students who claim to have uploaded a damaged file etc...) . Oh ya aswell as a automated emialing function that will email the student as soon as you've finished updating there mark's or feedback.( not relying on the cron job , but if this is nessacery i will code it in ).
I should be finished within a month or so ( very busy at work cant spend all my time on it . ----You never know might have it finished this week ----)
If you would like i will post a copy to the forum...