Can I save my setup of slots and hotkeys?

Yes. Click on "Schemes" in the menu and select "Save Scheme". The current scheme is now available for any later session with CombiWave. Please note: a scheme saves paths of audio files and not audio files themselves, which basically means you can use schemes for CombiWave only on your local PC. If you want to transfer a scheme and all related audio files to another PC running CombiWave use the export functionality.