Apparently it is not possible to grade a quiz by question (as opposed to by student) and upgrade marks for all students every now and then. Instead, upgrading can only be done after marking all questions for each student. I much prefer marking by question, as this makes my marking more consistent, faster, and reliable. I can compare different responses to the same question, and correct my own marking quickly if I detect a problem with the question design. I just can´t understand why Speed Grader won´t let me save and update my marks for the whole cohort of students every time I finish marking one question. If I need to interrupt my marking, I wouldn´t be missing grades for tens of students at a time. This is a most needed feature. Please consider it.