Can I use Realitone products in Music Libraries?

Absolutely fine, provided you’re using Realivox or RealiBanjo in legitimate songs or cues. They don’t even have to be good songs, but they do have to be actual songs (or cues), as opposed to a sneaky attempt to make a sample library with our sounds.

It is also perfectly fine to have Realivox instruments exposed solo. As long as it’s what any reasonable person would consider a legitimate use, then it’s allowed.