I actually came here for the same reason. I am having the same issue with the CGS 28 modules on the Canon Engine.
I am running on 15V.
At first I was having issues with only one of the 3 CGS 28 modules working. I swapped the chips from the working module to the non-working ones and tracked it down to the TL074. I tried the circuit with numerous TL074's and only a few would work in the actual circuit properly. Some had issues with working up but not down and vice versa. I had no issue using the "bad" TL074's in completely different modules than the CGS 28.
At first I was having issues with only one of the 3 CGS 28 modules working. I swapped the chips from the working module to the non-working ones and tracked it down to the TL074. I tried the circuit with numerous TL074's and only a few would work in the actual circuit properly. Some had issues with working up but not down and vice versa. I had no issue using the "bad" TL074's in completely different modules than the CGS 28.
I should also note that I also note that I am having the same issue with the UP and Down. I can not get any of the working modules to Reset when in UP mode.
I am also having issues with the CV output and Inverted where if more than one Sequential Switch is triggering on the same step at the same time there is a drop in the output CV.