The Euroversity Network project (2011-2014) has built a Good Practice Framework (GPF) that functions as a heuristic for course and activity designers wishing to develop courses and other materials for use in a range of virtual worlds. This framework has been tested with a number of courses during the running of the project and the aim is that it will be useful for new designers as a starting point for their own ideas development. The GPF is still open for adjustment and negotiation and this paper shows how two new case studies that were not the direct focus of the project, minority languages and elder learners, help to expose some of the framework's weaknesses, but also many of its strengths. These case studies illustrate that a tool like the GPF can provide an effective mediating function for a variety of courses and other activity in virtual worlds. [For full proceedings, see ED565087.]