GS(General Schedule)-06-07 Questionnaire: How does the percentage really work?

First post on here, so bare with me:

I'm currently running into a snag with the questionnaire portion for "Military Personnel & Administrative Assistant" that can either be a GS-06 or GS-07, so as I answer the questions I can fully answer all of them comfortably as D(I have performed this task as a regular part of a job. I have performed it independently and normally without review by a supervisor or senior employee.).

Now after this is all done I wait for the status of the application to go through, but it keeps getting kicked back saying "You do not meet the minimum education and/or experience requirements for this specialty and grade."

What I did next was personally e-mailed CPAC(Civilian Personnel Advisory Center) here on post, and they gave me the response that the questionnaire needs to be 95% or above in order to go through the next screening process, but if you answer E on the questions you need to back it up with more documentation, and my resume states what I've done--I just don't fully understand how this questionnaire works to be honest and what I'm getting at is what is the percentage at with all questions answered as D; do I really need to answer some of the questions as E?

I've also asked my colleagues about this issue, and no one really seems to know, but have had similar cases of their own on the matter at hand. I then again contacted CPAC about this issue, with a vague reply once again saying it must be my resume now... So it would seem, that CPAC itself doesn't even know for a fact why it got kicked back.

I'm also currently a WG(Wage Grade)-06 right now if that has anything to do with it, but I've preformed as a GS-07 Supply Tech(I have all SF-50 documentation).

Any guidance on this issue would be greatly accepted and thank you for the insight.