Symptoms
WP Toolkit Deluxe or WP Guardian (Plesk addon) show an Upgrade button and some locked sections when using the Web Admin license.
Cause
WP Toolkit is only included with Web Pro and Web Host licenses. When using the Web Admin license, it's also necessary to purchase the standard WP Toolkit along with WP Toolkit Deluxe or WP Guardian (Plesk addon).
Resolution
To unlock all sections when using Web Admin, purchase WP Toolkit.
This will be fixed in the future under EXTWPTOOLK-10467, which has been filed to prevent confusion by requiring the purchase of WP Toolkit before being able to buy the add-ons.