Update: I love MS chat support.

[Imaginedvl]

Mr Puggsly said:

Imaginedvl said:

Exactly what I was thinking. When you started to talk about Phil Spencer, I almost stopped to read... 
The support guy is supporting the Xbox One system itself and the question about the game dev. was fair and the guy was just trying to help the way he could with the tools  available to him. Going in jerk mode like this is not really helping.

In any case, weird problem. One thing you can try is to download it from somewhere else. I know it may not be that easy but at least you'll know for sure if the problem is coming from the internet connexion or not.

I don't think that makes much sense considering I've downloaded many files on Xbox One already.

The bandwidth usage also shows a lot of data is transfering but the download itself keeps resetting to 31%.

As I was sleeping the X1 bandwidth usage says over 25GB downloaded. Yet the download has stayed the same. I've cancelled and restarted the download multiple times and it gets stuck at 31% every time. Doesn't that seem like a bug?

Definitely seem like a bug but what I'm saying is that by downloading the file from another location and getting the same issue (or not), it will at least help you find out where is the issue. Is it your connection or something specific to your home configuration or not for instance.

Another thing you can try if you have a USB Harddrive, is to download it another location (instead of the internal HDD).