Thanks to MasBart, I updated the earlier version to normalize signal and lead according to vigor and trigger. Vigor and trigger are limited to +-2. Now signal and lead are also in that range.
The code of interest is lines 39-43:
tmpdif = (BP - nz(BP[round(period/2)]))/close a = array.new_float(0) for i = 0 to win-1 array.push(a, tmpdif) den = array.max(a)
den is then used to normalize the BP values (bandpass filter).