Thank you for bringing this to our attention.
This issue is related to high server load times during the snapshot capture. The image processing will not happen during high server loads. You may have notice clicking the 'Reload' restores the 'snap shot' for the session.
Usually after the first success the image is saved inside the database and should work from there afterwards. As an additional measure, you can clear your browser cookies and cache. This will close out any faulty sessions. This will not be required every time, however, if this message appears again, quickly refresh your browser.
Kind regards,