Hi,
Uhm... have you asked the asset store?
usually, when you buy several license, it's because you are sharing a project amongst a given number of developers, and so you are the owner of the project, developers access your project, and PlayMaker is already installed in that project. That's ok, License is per seat, so one developer goes, you bring another one, it's still the same seat.
If that developer wants then to use PlayMaker outside your project, he's then supposed to purchase PlayMaker too. the same is true for 99% of asset store items.
Bye,
Jean