If you want to backup all your presets, you can export one by one al the banks you want to backup. Alternatively you can backup them all with a single operation.
1. Open THU.
2. Click on the burgher menu by keeping pressed the Option key on Mac, or the Alt key on Windows. More options will be displayed in the menu
3. Choose "Reveal user data files". A new window will be opened.
In this window you can find a file named presets.db
That file contain all the presets of the plugin.
3. Copy that file in a secure place and when you want to load all your presets in a different Computer just place this file in the same folder in the new Computer.