As has been explained in previous news updates, there is no tech progression in the mod. Each Galactic Conquest scenario relates to a specific era (tied to an Imperial leader) with units and heroes relevant to the period. Thats all.
If you are playing the Art of War/Lite Galactic Conquest you can advance through the eras in a style similar to tech progression (in that the units and heroes will change depending on the era). To do this you have to kill off the current Imperial leader (this is true for both the New Republic, Imperial Remnant and Empire of the Hand).
Note: Art of War is the largest Galactic Conquest in the mod and will lag on lower-end computers.