In my Audio Plug-Ins user's folder I can see nothing of them:
I added a new AU called TB_Isone.component into /Users/roberto/Library/Audio/Plug-Ins/Components then I delete the file com.apple.audiounits.cache from the path /Users/roberto/Library/Caches and finally started GarageBand, it opens telling me to refresh the AudioUnit section (GarageBand is going to execute the scan of 25 Audio Unit installed! --> why 25 plugins ?)
If I try to add a new master effect from the list of "Effetti Audio Unit" I can see the following:
Then the TB_Isone Audio Unit is recognized by GarageBand and I can use it.
Unfortunately doing the same with Pianoteq 4 STAGE.component doesn't work (copying it from /Library/Audio/Plug-Ins/Components/ to /Users/roberto/Library/Audio/Plug-Ins/Components/ folder).
How could I do to solve this issue ?
iMac, Mac OS X (10.7.5), Total amount of RAM: 12GB!