First i would suggest that the 'Recovery Codes' section should be made very obvious and stand out on the page, bright colored or something, it was very easy to miss when under pressure to get the account setup and configured to interface with a client so i didn't even see them to download them.
Second, if you didn't download or have lost recovery codes the recovery of the account can only be done with the SSH Key and using a bash terminal. The instructions of which are geared towards Linux users, my client was using OAuth and didn't have an SSH Key in (although one was associated).
It has taken a considerable amount of time to figure out how to get the bash working in windows, how to get authentication in windows bash and how to attach the SSH key to the authentication bash to get the recovery codes. - Could you not provide some picture instructions for windows users? Or even just upload your key and password here page and we will display your recovery code?
Also finally, is it possible to have another method of recovery? Perhaps SMS Message and secret code or something?