Restore to a point prior to the update engine breaking, make sure it is stable, and then apply each patch separately until you find the one that causes the problem. I know this will take time but it definitively identifies the update that breaks everything and it takes less time to go through this than to try to identify which of how many later patches could have caused it. That being said however I would check if you have a nvidia driver just before updates started failing and try backing that one out first before the more drastic step of restoring to an earlier point in time. Just remember..don't get impatient, if you remove 3 patches and the problem is fixed which one was it. better to do it slowly and methodically. The results are usually better and the knowledge gained is vastly superior.