For everyone not running PBXact who sees the error saying PBXact License is not supported, they can upgrade System Admin to the current stable version to resolve this issue:
fwconsole ma downloadinstall sysadmin
fwconsole ma list | grep sysadmin
| sysadmin | 15.0.15 | Enabled | Commercial |
edit - and now PBXact is supported as well.