I have to upload the CPS scores in two batches, one for the morning section, one for the afternoon section. In doing so, I think Webcourses overwrites one section's scores with zeroes, and this might be why so many of you have been asking about mysterious 0 when you know you were present and clicking.
Not to worry. I have all the raw scores, so nothing has been lost, and I have never been defeated by Webcourses or CPS. I shall prevail!