Hi,
We also use G04Schools for our internal assessment & reporting. We will attempt to upload the results into the actual column, then let GO4Schools do the calculations but I have experienced the same problem as you.
I was given the data in a CSV file to upload into Go4Schools as a dry run to ensure it works. I had no problem with subject names that match e.g Mathematics was the same name in the results file however we have so many subjects where the name is incorrect due to Go4schools feed rules, or the subject simply does not exist.
To add to this problem the QUAN codes are also not correct, e.g I have Business Studies using a QUAN code for Japanese. I'm going to spend a long time going through each subject correcting the Quan codes.
I am sorry you have also experienced this, but now I know I am not the only one. I hope this year results day goes smoother for you.