You can add sounds from your personal sound library by going to the user folder in the drum or loop browser and selecting the User section from the Pack filter, then pressing the Import icon. This will launch a browser that will allow you to choose sounds from any location on your device. See image guide below.
Step 1: Tap the Pack Filter Menu
Step 2: Tap the Pack Filter Menu and select User
Step 3: Tap the Import icon
NOTE: If you select "User" in other than the drum or loop browser (e.g., patch browser), the Import icon does not appear.