[NTG-context] Modes for configuration

Following the example in the ConTeXt Wiki (http:// wiki.contextgarden.net/Modes) I have defined an environment file that specifies two modes (screen, print) for the production of the same source file. This works well when the appropriate texexec commands are given at the command line. The problem is that I am trying to set this production up for users who are happier with a GUI. Is there a way to do generate diverse outputs from the same source file without resorting to the command line? I have experimented with TeXShop—the users tend to works on Macs —but without success thus far. Thanks for any suggestions. Alan