I have the same issue. Since I see a number of folks saying they're using Windows 10 I tried a Dell Mobile Workstation at the office that still has Windows 7 on it and it still crashes upon trying to log into Twitch. I'm going to try Open Broadcaster Software on this machine as I had little luck getting it to recognize as a video capture card on my Windows 10 machine (no video would pass through to OBS, though it would show up in Capture mode in the Roxio software).
I'll add that I have installed the 2.1 update. This is a new purchase I just received yesterday, so I don't have a "it worked previously" story, heh.