From your description it seems like the rebuilt clutch may be too strong on the springs, too much or too little friction material and the release bearing itself may be lazy. The clutch is engagement and take up is controlled by the egear ecu from engine speed and torque data and also wheel speed and transmission input shaft speed. The engagement is then regulated by the egear ecu via the clutch solonoid valves which control the amount of movement required by the clutch release bearing for a smooth take up and also smooth drag.
Have your workshop checked and adjusted the clutch point of initial slip(PIS), this determines how the clutch take up and engagement is setup, the adjustments can be harsh or soft, harsh usually ends up stalling the engine and result in jerky slow speed engagement and shifts.
It is not a good idea to replace the clutch with a used part, they are usually worn.
Best to stick with a stock clutch and release bearing if replacing, then bleed the egear hydraulics and setup the egear ecu PIS.
Hope this helps