Q: Can't open "MS Office 365 University"with Yosemite

I downloaded MS Office 365 University, installed the application as normal, opened the MS Office Setup Assistant, and followed instructions for activating it (Link: "Sign in to an existing Office 365 subscription"). But after entering my username (=email address) the assistant would not connect with Microsoft. I contacted Microsoft support, as follows:

1. Chatted with "Donald" at support, who provided a number of suggestions (reboot, reinstall software, etc.) but to no avail. He suggested I call tech support.

2. Called tech support and talked directly with a very patient IT rep. We tried a number of fixes, to no avail.  He then asked if he could enter my computer remotely, and gave me the URL to download the relevant APP. Downloaded the app and extracted it, but it would not open. After more than an hour trying this and that, we hit a dead end.

From what I've picked up on the WEB this appears to be either MS or a Yosemite problem.

Anybody found a workaround?