Hi Dani,
The waveform field should be blank for all presets after you send the "Space Scapes.theremini" file to the Theremini using the editor. Maybe you forgot to click the "sync" button and that's why you are seeing "etherwave"?
I didn't keep track of the waveforms I used for each preset. I was using Midi-Ox to switch through the 12 waveforms and the Moog editor for changing the other parameters.
I asked Moog during beta testing if they would consider publishing a Midi Implementation Chart. They said they had no plans to do that. I was told that Sysex implementation of a preset dump would be difficult to do because of how Moog does encoding. Analyzing the theremini files I couldn't figure out where the waveform is listed.
Good luck on your midi-controller.
Gary