Does that mean that once you make a copy from a source you have the right to copy from, then you cannot make another copy from that copied source? It doesn't seem like the wording of the law is saying that though...
...all archival copies are destroyed in the event that continued possession of the computer program should cease to be rightful.
This part seems to imply that your rights to the copy are actually independent from the original copy or physical media. It implies that i can have as many archival copies as long as I have the rights, so I can't see why I can't download a copy as long as I don't cease to be rightful in doing so.