Is the problem with any character, or just V4?
I use the latest C6 standard and am not having any inj trouble, BUT DAZ changed V4 so that you have to load each and every morph.
If that is your problem, then look over at April YSH's website (She is the vendor responsible for so many of the fine hair models at DAZ). She has a freebie patch that loads all the morphs on V4 for you. You can preload a V4, save it as one of your objects in the browser, and be spared this trouble in the future.
If that is not the source of the trouble, I defer to the C6 pro folks.