Adobe Digital Editions Questions

Hi!

I would like to ask a few questions about how Adobe Digital Editions works.

Firstly, if I buy an ebook (DRM) and download the ACSM file without having  Adobe Digital Editions in the computer or without having created/logged in the Adobe ID, will I be able to, after downloading ADE, activate an Adobe ID and have access to the ebooks in different devices, or will the ebook  be just authorized in one device?

Then, I would also like to know if, for some reason I change my devices more often, because I change computers, or a device is broken, I will  be capable of de-authorize the older one and access my ebooks in a new computer/smartphone in a easy way.

Finally, can ACSM files and Epubs me moved (or copied) to a USB pen, for example? In case, I loose my device it would be useful to have access to my ebooks.

Thank you very much for your help.

Jorge