Error Message in GarageBand

Hey all, I also need help! I'm running 10.6.8 on my 2009 MacBook Pro (2.6 GHz Core 2 Duo, 4 GB RAM) and I'm experiencing problems with GarageBand. When I open a file, I can't play it, export it to iTunes, or do much of anything really. I get this error message:

Disk is too slow. (Prepare)

(-10001)

I've read several suggestions to correct this problem such as:

1. Cloning my hard drive to an external HDD, re-formatting my internal HDD, and then reinstalling the clone back onto my internal HDD

2. Doing a complete uninstall/reinstall of GarageBand

3. Using an external HDD that supports Firewire 800 to run EVERYTHING on GarageBand (I'm currently running the audio files from my internal HDD and using my external solely for storage because its USB 2.0, which I find appallingly slow)

4. Repairing the disk permissions (I ran the "Verify Disk Permissions" on the Apple Disk Utility and found a laundry list of groups and users that differed)

5. Call Apple!

I should also point out that everything was working fine until one day, when I received a warning saying that my HDD was nearly full. I only had a few MB left on my 150 GB solid state HDD, so I purchased a 500 GB (5400 RPM) external and freed up around 60 GB by moving all my GarageBand projects and my movies to the external. I rebooted the system a bunch of times, but I'm still experiencing the same problem. Repairing the permissions seems like the easiest, most painless solution, but I've heard of the dangers of doing this and I'm not sure that it would fix anything. Any help would be greatly appreciated!

Thanks!

I'd suggest step 1 actually, or you could try moving the GB project you're working on to the external as well.