Upload & Sell: On
This is what I got from that thread from andrewho:
The preferences file is the com.adobe.Lightroom4.plist file, located in [user name]/Library/Preferences.
The [user name]/Pictures/Lightroom folder contains:
Lightroom 4 Catalog.lrcat, the Lightroom database file
Lightroom 4 Catalog.lrcat.lock, which prevents you from overwriting data
Lightroom 4 Catalog Previews.lrdata. which contains preview data for your photos
Catalog backups are saved to [user name]/[catalog location]/[catalog name]/Backups/.
Installed and custom presets and templates have filenames ending in .lrtemplate and are located in the [user name]/Library/Application Support/Adobe/Lightroom folder.
Registration data is in Library/Application Support/Adobe/Lightroom/.
Important: Apple made the user library folder hidden by default with the release of Mac OS X 10.7. If you need access to files in the hidden library folder to perform Adobe-related troubleshooting,
adobe said some slow LR issues were due to a corrupted lightroom profile. i deleted mine and it sped up quite a bit. your mileage may vary
LR4 seems much quicker now, more responsive!