For $4.99, I can get the Garageband 10.0.3 with more features and better loops to create music on Yosemite 10.10.1, but I couldn’t finish installing the software, it took forever to download and break in the middle for some reasons even though I have high speed internet. After Googling for a long time, I’d read a post that someone had successfully installed the Garageband with the same problem. I can’t seem to find the post to give credit to the person. Anyhow, here is how he/she did it.
1. Remove all Garageband.plist in ~/Library/Preferences/
2. Remove the ~/Library/Caches/Garageband folder.
3. Remove the ~/Library/Containers/Garageband10 folder.
After doing all these, the Garageband 10.0.3 works right away with all the loops already installed. BTW, the Garageband 6.0.5 is still working in a separate folder.