That explains it, adding the comp adds weight to the barrel and holds the slide locked for longer after the bullet exits the barrel, once the slide unlocks there isn't enough energy left to cycle the slide. You either need a lighter recoil spring or hotter ammo.
If I were you I would get some more appropriate powder before proceeding, some Autocomp, CFE Pistol, Silhouette or HS6 will do the trick for you.