So you have 3 layers. Are the 3 layers assigned to the same MIDI channel or a different one?
If can have up to 16 layers in a snapshots, assigned to the same or different MIDI channel. If you want to change from an “instrument” to another one, the faster way if change the MIDI channel where you send the playing (note-on/off) messages.
Also, you can send Bank/Program Change messages to a given channel. it will change the bank/preset for the layers assigned to this channel.
Could you give more details about what are you trying to do?
Why don’t use a Program Change message? It’s the logical choice …
Control Change messages are not commonly used for that. Anyway, from the webconf tool you could add some rules to the MIDI router/filter, remapping Control Change messages to Program Change messages.
Finally, you could use the Master Channel to load a new snapshot. But it takes longer …