Hey Probasco,
My dad had a very similar problem to what you described today. He did this weeks updates this morning to his snow leopard mac tower with some huge processor stats on it. He has terabytes of .mov footage that he shoots with his JVC HD cam (very professional looking) and captures with a 5 or so year old looking little HD drive attached to the camera with firewire 400. Anyways, this morning I was managing some of his media throughout a handful of external and internal HD's when I starting seeing a General Error in FCP. It had no numbers or anything just "General Error." After many experiments and scaring my dad half to death thinking his HD's were possibly corrupted (this problem did have that behavior so I couldn't rule it out quite yet), the solution has finally surfaced.
Fortunately, I have access to a plethora of macs running different versions of OS's even as different as just a month ago Snow Leop and Lion. So now after spending the day on that project and a free dinner from my pops I can share the solution in case this weeks update has caused some mayhem in yours or others computer environment.
What you'll need: [2 system folders: Macintosh HD/System/Library/Components
Macintosh HD/System/Library/Quicktime ]
I took both of those folders from the Snow Leopard iMac that still supports all of his projects and footage (last update in September I believe on that one), and put them in the newly updated Mac, well I did it to his MacBook too which he had updated this morning as well. I actually hard deleted the two folders from the new updated computers first and then dragged those 2 folders in.
That's the first part, then restart the computer once or twice and then its back to normal. If I left out any details that you wish to know about or if I was unclear about anything or you want those two **** folders! then feel free to contact me if this forum allows that. This is my first time posting anything in a forum I think or its been awhile.
All the best,
mojotreetop