You manage your Add-ons from the Add-Ons tab.
This can be accessed by pressing Setup, Config, then Add-ons
The green check mark next to the Add-on pack, indicates that the Add-on is activated. (See above)
A lock symbol indicates the Add-on pack requires activation. (See below)
Instructions on how to upgrade your console, are available from the downloads page, in your shop account. https://shop.allen-heath.com/index.php?route=account/download
To use your add-ons, press the Library button, on the processing tab relevant to the Add-on (for Compressors, this would be the Compressor tab, for Preamps, this would be the Preamp tab) and select your Add-On from the list. Then press Recall.