I did my first preset to learn how the E1 works. It has the following shortcomings:
Requires Device ID to be set to 0.
Requesting a preset dump from the device works, but it is not parsed (Since the Patch Editor online tool does not allow to parse multiple SysEx at the same time.
When Loading a Snapshot, there is not enough delay from certain SysEx controls (or a way to skip them from being saved or loaded) and makes the Reface CP get stuck without reading some controls.