Hello Steve

Can you please double check if you are on v3.0.3, and if you are purge all cache from your website.

If that doesn't help, please provide me the Google Spreadsheet link and the Excel file you tried to upload (Excel files have to be uploaded, not used online), and then please provide me a temporary WP-admin login for your site where this happens, so we could log in and take a look ‘from the inside’ as that’s the most efficient way to see and resolve the issue. We do not interfere with any data or anything else except for the plugin (in case that’s a production version of the site), and of course we do not provide login data to third party. 

You can write credentials here just check Private Reply so nobody can see them except us.

Hello Steve

I can create a table linked to that Google Spreadsheet file without any issues:

If you still can't get it to work, please provide me the temporary WP-admin login, so I can check.

You can write credentials here just check Private Reply so nobody can see them except us.

Hi again Steve

You can add a Formula Column that would calculate the average per row, if that's what you mean?

Then, you would be able to include that column and plot it on a chart.