The NethServer 7 Final release is still not scheduled. We’re working on rc3, and we hope CentOS 7.3 is going to be released soon. We could build our ISO on it, and would be a nice thing because it reduces the pending RPM updates after a fresh installation.
No, not at the moment. But if you want to test them, I can fix them next week! Would you want to try?
As said by @filippo_carletti, that WARNING can be ignored. I also say, if you go with ns7 you won’t see it anymore!