Peter, thanks for your thoughts
About the first one, that is a good one, we will try to work on it soon (by the moment you can only specify the due date of the task and if you let the students to submit their answers after the due date)
About the second one, the problem is that the assignments (projetcs, exams, etc) are assigned to all the students/groups in the class. By the moment, there is no way to assign a project to a specific group. You can assign the project to all the groups in the class and grade them according to their work, but the project is assigned to all the groups (At the end, this is the same that the individual tasks, in fact, you can create "individual groups" in case it is necessary)
Thanks again for your comments,
Jose