Now on a less practical note, I'd argue that the letter of the law does not prohibit what you did. Here is part of the copyright code:
So owning a copy does permit you to make a copy of the program in question. Nothing in that language specifies that the copy of the program has to come from the copy that you own. Bits are fungible. So by any sensible interpretation of that text you are legally OK.(a) Making of Additional Copy or Adaptation by Owner of Copy.— Notwithstanding the provisions of section 106, it is not an infringement for the owner of a copy of a computer program to make or authorize the making of another copy or adaptation of that computer program provided:
(1) that such a new copy or adaptation is created as an essential step in the utilization of the computer program in conjunction with a machine and that it is used in no other manner, or
(2) that such new copy or adaptation is for archival purposes only and that all archival copies are destroyed in the event that continued possession of the computer program should cease to be rightful.
Now I have to remind you that the law is seldom if ever sensible. What really matters is how many lawyer hours you can afford. If, on the infinitesimally small chance you were to get sued for this, a judge could realistically rule either way. But that won't happen, no one has ever been sued for anything like this.
BTW, on an ethical basis you are 100% OK here. You have supported the developers, and that's the important thing.

