If the setup of the grade average is correct and it appears with a value on the student's Academic Profile, check to make sure the grades selected on the custom transcript in Transcript Builder match those selected to be included in the grade average.

If the grades selected do match, then it is likely something changed from the initial development of the custom coded transcript and needs to modified. Contact Blackbaud K-12 Support if the Professional Services team developed your transcript, otherwise, you will need to contact the entity who did.