"A bit of a Swiss Army knife..."
This plugin does various stuff. It's main aim is to make running multiple emulators for each system as easy as possible. You can setup all your emulators in GEmvoy first - running and testing them from there before dovetailing with GameEx. You can also choose which Emulator to launch a game with from GameEx itself. Lots of additional stuff. Best way to find out what it does - download it and have a tinker - it's very low impact on GameEx; your game and asset