Don't know how to lock out other users unless you put it on it's own network. As for the rest of it.
If you use a password to log onto your network, and cast straight from desktop to chromecast you should be fine. The way I understand it.
Sent from my PHOTON Q using XDA Premium 4 mobile app
Screwed by Google. Canceled ICS upgrade on my Moto Photon 4G. and No Update for Photon Q for Kit Kat.
Motorola Photon Q 4G LTE - CM 11.0 M8 - On ting.com - only Pay for what you GET.
Sprint Samsung Galaxy Note 3 Kit Kat, Stock rooted, twrp recovery. "too new for ting"
Nexus 7 2012 Kit Kat, Stock rooted, twrp recovery.
Retired, Kids Toys, Gave Away &/or Bricked; HTC G1, Samsung Moment, 2 Photon 4G's, Samsung Nexus S 4G, Kindle Fire.