My primary confusion is what the range knobs are meant to be doing. If you adjust upper or lower, in Range mode, the values of the range knobs are linked but I don’t understand how they interact. CV mode is the only one that makes sense.
Only “Raw” mode makes any sense to me. Quantize mode is just bizarre, pictured below. At the boundaries it introduces a higher frequency sawtooth modulation.
I also found working with the range knobs quite confusing. But in quantize mode simply any time the input signal hits a boundary the output CV (V/Oct) is corrected by 1V or 1 octave. Also you don’t need an extra quantizer in quantize mode. The quantization is taken care of by Fence. Listening to your patch made things a lot more clear to me.
Everything above C7(max) is reflected back (folded) over 1 octave (C7-C6) as soon as the level is lower than C6 it lowers to the minimum C1 and below that it is folding it back 1 octave (C1-C2) until it is higher than C2 etc…