De-authorized an anonymous activation and lost access. Can I re-authorize w/ an existing ID?

I made the mistake of de-authorizing my anonymous activation. However, I only lost access to the book I fulfilled through that device (PC) and the other book I fulfilled through another device is still accessible on the PC. What does this mean in terms of my PC's Adobe Digital Editions? I know that I cannot access that lost book again, but can I re-authorize my Adobe Digital Editions with an existing ID this time like so:

Will doing this cause any problems? After my experience of loosing access to my book just because I was trying to make it accessible to other devices (but took the wrong route of de-authorizing my anonymous activation, which resulted in lost access), I'm wondering if I should just make a new Adobe ID. I feel like my ID is messed up now and wondering if it is?

Finally, why is the book I fulfilled on another device still accesible on my PC, even after the whole de-authorizing an anonymous activation situation?