If I understand, you're saying people use your site to do a bit of video editing. In this case, I guess the purpose of registration is to save user state, beyon

If I understand, you're saying people use your site to do a bit of video editing. In this case, I guess the purpose of registration is to save user state, beyond sessions/cookies. Therefore, you could simply have a 'save' button, only asking for name/pw once it has been clicked. This way its up to the user to decide when/if to register.