Anything is possible, but if the update broke things, I would think there would be more complaints on the forum. It's been in the Betas for a couple months, and the older 12.12.3 release for several weeks. I've used my interface with at least three cars, one CAN and two K-line without incident, and I'm on Windows 8.1 as well. Also, from what I understand, the update was issued primarily to fix a very specific K-line comms bug that shouldn't affect your CAN-based vehicle.
I know it's not what you want to hear, but it seems likely to be something localized to your workstation. Did anything change there? Anything that hogs CPU, like a virus scanner, or anything that messes with power management/CPU state can affect the real-time responsiveness needed by the vehicle diagnostic protocols. If you were running on battery, if possible, try doing a scan with your laptop plugged into AC power from your house/garage. It can help prevent the CPU from aggressively throttling down to save power. My laptop definitely does better on AC power.
Jason