Save all settings into a backup file before modifying them. This way you will always be able to revert to your old settings if anything goes wrong.
Cacheman creates automatically a backup file for every user on first program start, so you can always bring your system state back. If you decide to uninstall Cacheman the first backup will be restored automatically.
Additionally to setting backups, you can also create System Restore Points from here.
System Restore is a very handy application. It creates periodic snapshots of your critical system files (like the registry files, COM+ database, user profiles) and stores them as a "restore point." If something important gets corrupted, you can revert the computer to the state it was in at a restore point.