Serious glitching/crashes, unresponsive UI, since 10.10.1 upgrade

Question

Has anyone else had this problem?
My MacBook Pro (Mid-2010 17" i7 model) was doing weird things on 10.10, so I updated to 10.10.1 (the updater would hang at 40% for ages, so I was forced to download the full installer), and since then, the Mac would randomly glitch out and crash with this kind of pattern on screen, causing the UI to become unresponsive aside from the mouse cursor.
Luckily I managed to keep it stable enough to clone the entire system partition to an external (though Carbon Copy Cloner reported at least one read error, on a disk file used by VirtualBox), which I'm currently booting from to do tests and attempt fixes, but whenever I try to boot from the 10.10.1 Recovery Partition it'll crash like this before I even get a chance to verify/repair/reformat the main partition. Occasionally it'll crash like this if I just boot from the main partition normally, and interestingly, I created a bootable Yosemite USB key using a brand-new 16GB USB key and it crashed like this as well. The only drive that hasn't crashed so far like this is the clone on the external partition.
At the moment I'm almost forced to downgrade back to Mavericks (currently preparing a bootable USB key), which was far more stable, but before I resort to that, does anyone know what this could be, and if there's an easy fix that doesn't involve nuking the whole drive from orbit?

Answer 1

Hi Terry,
You'll need to either trash or update your Saft plugin. It is located in 'HD/Library/Application Support/SIMBL/Plugins/'. SIMBL might need updating as well.
Yang