Note: If you're looking for an even better Casio CZ editor, check out CZ Touch, for iPhone and iPad.
This app is a stand-alone Casio CZ-101 patch editor built using Max/MSP. It is meant to give easy access to control all the parameters that are saved with a preset on the CZ-101 (which is pretty much everything except bend range, portamento settings, and tuning settings).
Any changes made on-screen are instantly sent to your CZ via your MIDI interface. You can then save your changes to a patch on the synthesizer (using the normal method on the synth), or you can save your patches in the editor itself by shift-clicking on one of the empty dots in the Presets section on the left. Click on a filled dot in the Presets section to switch to that patch.
The editor is made available as an open-source Max patch, now hosted on Github: https://github.com/coffeeshopped/casio-cz-editor
Also, if you'd like to know when I update the editor, or make new ones, join the Coffeeshopped Newsletter.