If you set "Command" in Command Center to "None", this would switch to your channel 1 (with my Engl Powerball, it works that way).
Unfortunatly this does not work with snapshots, since the FX does not accept "None" and Ext-Amp as values in the same pre-set.
If you want to switch from clean to the other channels, you have to use different pre-sets instead.
In my opinion, this is clearly a bug in the Helix Software. I cannot understand, why the device does accept 01 + 10 + 11 but not 00 as Tip / Ring values.