Ok, I talked with our extension programmer, and apparently this is a new issue with the most current versoins of Chrome (for example, Version 27.0.1453.94 m).
The issue is already listed with Google, and apparently the fix should come in a future update. However, we can't be sure exactly how long that will take.
Considering that non-supporters can only see a limited number of weeks in their training history, at this point we recommend that you either try a previous version of Chrome (e.g. Version 26.0.1410.64 m), to upload these training results. Alternatively, Firefox should work, and you can use that in the interim.
I'll try and post again here whenever the Chrome update arrives to fix this.
Sorry for the inconvenience!