When you are connecting to a remote computer located in a closed corporate network that is inaccessible from the internet by default, RD Gateway may come helpful. In these cases, you need to set up an RD Gateway in Remotix connection options.
If you travel to and out from the corporate network with Remotix onboard, you may want to ignore RD Gateway tunneling whenever you are in the same network with the target computer.
Note that you may only use RD Gateway when SSH tunneling is disabled (and vice versa).
For more information on Remote Desktop Gateway, see What is a Remote Desktop Gateway server? and Overview of Remote Desktop Gateway.