I do the old port forwarding trick and it works great, Except i haven't gotten DD to launch and work properly for smiledesign and splintstudio. But normal design of C&B, rpd, denture and implant works no problem.
But remote site must have qualified spec PC and decent internet speed. Go to the facebook 3shape study group and look for portforward by Przemek. Not too hard to setup just need to understand basic IT.
Globalproject is the VPN 3shape uses, you can use silex technologies had a usb lan box you plug you dongle in and can connect from anywhere. But read limitation one user at a time via the device, unless you get the next model up.
DS-600 is designed to easily connect and share USB 3.0 and 2.0 devices over a network, allows flexibility to place the USB device anywhere on the network
www.silextechnology.com