svmariscal: or do these games' rights have to be acquired on a per case basis?
They do, sort of. GOG can only sell games that are part of a specific contract with a publisher. Whether other Dynamix games are already part of an existing contract, and just haven't been released yet, is something we don't know, and GOG won't tell. If they are not, a new contract would have to be negotiated with whoever owns the rights to them.