When you say "first download" which one are you talking about? The first thing to download should be the EnB client. If you try to download the Net 7 setup first, it will fail without EnB Client installed first.
I just downloaded about a week ago, I'm also on Windows 7 and got it to work. (Not that this information is helpful, but just to let you know that it can be done)
I hope you do get the game working, this game is like crack. The good kind. Not the stuff that makes you scratch at your arms and live in alleys.
I'm sure you have already found it, but just in case, check out:
https://enb-emulator.com/index.php?/topic/714-install-enb-from-scratch-instructions/