Virtual environments lack a standardised interface between the user and application, this makes it possible for the interface to be highly customised for the demands of individual applications. However, this requires a development process where the interface can be carefully designed to meet the requirements of an application. In practice, an ad-hoc development process is used which is heavily reliant on a developer's craft skills. A number of formalisms have been developed to address the problem of establishing the behavioural requirements by supporting its design prior to implementation. We have developed the Marigold toolset which provides a transition from one such formalism, Flownets, to a prototype-implementation. In this paper we demonstrate the use of the Marigold toolset for prototyping a small environment.