Yes! You can treat Mainstage as an External Sound, essentially routing any RMS Keyboards channel to Mainstage to take advantage of your personal collection. Best of all, when you do this, you maintain any of the splits, layering, and mapping we've programmed.

You first need to set up Mainstage to receive data through the IAC bus. Here's a video that explains the process.

Once this is done, use the External Sound feature to route any given channel to Mainstage.

Note: using RMS Keyboards together with Mainstage can take up a lot of memory and CPU. Not all computers will be up to the task, depending on the external data used. Be sure to test carefully outside of rehearsal/performance.