Sorry for the confusion. CNPF is silicone and sulfate free, so yes it's CG approved, and it doesn't have any ingredients that should cause buildup. I just haven't picked it up after going CG, and only used it a time or two before CG. If you're interested, definitely try it.
If you want another option, the pt linked in my siggy is both cheap and easily customizable. However, it's a "sometimes" thing (a deep protein treatment I use every 1-2 weeks) as opposed to something you can add to any product.
If you'd like proteiny conditioners, Ion Effective Care, Ion Reconstructor, and Cure Care are some Sally's options. Nexxus Emergencee, Aphogee 2-Step, and Joico K-pak are commercial pt options. K-pak does have mineral oil though, which some people's hair doesn't care for.
This was a recent pt thread: All time fave protein treatments? And best DT to use after?
If you do a search, there have been several threads about CG products from Sally's. Look for posters with similar hair properties and scope out what they use. Oftentimes those products will also work decently well on your hair too.