[IcyMidnight]

So I eventually just decided to reinstall my whole OS. It took me 3 months, but I now have a working USB video connection. Works fairly well. Too bad I had to resort to something so extreme to fix it.

If others are wondering if it's a configuration issue of their own here's something to try:
Use Disk Utility to shrink one of your partitions ("drives")
Create a new Partition
Install a new copy of OS X on the new partition and try installing the driver there. (This doesn't overwrite your currency installation)

That's how I discovered I could actually use what I bought.