International Student!! Common App help please!!

<p>Hello,
I had my principal fill out my common app counselor form today. In that I had a few doubts-
1. The counselor report required a GPA and a class rank; since my school provides none, could I leave those options blank.
2.She filled one form and then I photocopied it ten times and then got it stamped from my school. I also got a attestation but in a local language. Are these copies fine?
3. In the online recommendation, do the letters need have a letterhead or attestation?
Please help!!!</p>