Well why don’t you use a couple of BIGNUM operators, to figure out the relation between your knob and the resulting pre0 value, for instance? Then it’s just a matter of adjustments indeed. There isn’t much to be confused with if you just check the results visually. Also if you’re using delta from the encoders, you will need a MUL afterwards, to replace the step value - I do that a lot.
Edit: my mistake, you can do that for the encoder, but not for the pre0 (it’s in the input section, therefore it can’t be sent to a BIGNUM). You can still use one bignum on ENC0 with a step value of 16, and switch regularily to see the end result. Not so bad, I’d say.