Nope. No idea where to get a previous version.
Actually, when I began this thread, my original post's first sentence was this...
Yep. It was your response to them that wasn't really needed. I understand the frustration, though.

If it were my computer having difficulties, I would find out what was unique to my computer and make it right if at all possible. If not, I would try another bitmap editor to see if it works with EC7. Such as PhotoLine.

But have you tried using the 32-bit version?