I know that some people use VPNs successfully–TCP and UDP traffic must pass between the two machines freely, as if they were on the same LAN. Anything that might impede this (bad VPN, misconfigured VPN, or firewalls) is likely to break private zone streaming.
This piece of the system just wasn’t architected for remote access, but if you can get it working, it’s fine to use it.
We’ve discussed some neat ideas/architectures to solve the problem well. A remote access solution (that will not require a VPN) is on the roadmap, but we haven’t put a date on it yet.