This depends what you mean by the Type I/II cement being “sticky”. My suspicion with these type of problem is always that it might be connected with gypsum dehydration and temperature control in the different milling circuits. Are there major differences between the temperature regimes in the two milling circuits?
That’s not a big temperature difference. Residence time will also be important. Really the calcium sulphate mineral phase composition needs to be determined on the cement produced from the roll press circuit and the ball mill circuit