Hey Joe,
I have two expression pedals (I'm also using the Behringer FCB 1010 foot controller). I'm using one expression pedal (B) as a volume pedal, i.e., pedal is mapped to MIDI CC 7 (Volume). I have SL MIDI Bindings (under Preferences) set up so that CC 7 maps to command 'wet' (main out). In my case I have it enabled for Loop # 'All'.
The other pedal (A) I have set to CC 16 (General Purpose controller), but it only sends values 0 - 3 (four values) instead of 0 - 127 (128 values).
I have Sooperlooper MIDI Bindings set up so that CC 16 maps to the 'quantize' command. The values 0, 1, 2, 3 step through the possible settings for quantize of 'off', 'cycle', 'eighth', 'loop'. I did the latter because of a bug in SL (read more here:
https://sonosaurus.com/slforum/viewtopi ... cb7498c306).
I am sure there are other possibilities, these are just the mappings that I'm using.
Hope this helps,
Len