I have not worked with chemical kits, only with raw chemicals.
Kodak give formulas for developer working solution and replenisher.
Athiril colleague gave you the link.
http://motion.kodak.com/motion/uplo...t_en_motion_support_processing_h247_h2407.pdf
Effects of Mechanical & Chemical Variations in Process ECN-2 here:
http://motion.kodak.com/motion/uploadedFiles/h24_08.pdf
Effects of Mechanical & Chemical Variations in Process ECN-2 refers to certain types of film.
Probably for other negative color variations are a little different.
In my opinion, if you want to use just only replenisher developer for ECN II proces, no water.- I add 0.4 g / l sodium bromide.
If you have a ph meter check if you have 10.25 ± 0.05.
The development of the test stripe will give the answer.
Note
If these kits are slightly older might like color developer substance CD 3 have a lower concentration of the active form of 5.5 g / l.
So it is closer to 4 g / l.
No need to scare those graphics variations of photographic effect.
George