This add-on allows you to select user groups which are able to purchase each upgrade. The user must be in at least one of the groups allowed, and must not be a member of the 'not allowed' groups. If they aren't, the upgrade will not be visible to them.
This makes it possible to have hierarchical upgrades, upgrades exclusively for trusted members, etc...
This makes it possible to have hierarchical upgrades, upgrades exclusively for trusted members, etc...
