You can connect to your Timote server over the mobile network but it requires some knowledges about networking.
Timote uses the http protocol and doesn't require persistant connections. It should work behind a proxy, so you can select the port 80 if your provider is blocking the other ports on your mobile connection.
In the server settings in Timote, there is a “Force connect” option. If activated with the auto connect option, Timote will try to connect to the server automatically if it doesn't detect it on the local network.
If Timote detects the server on the local network, it will connect to it using the local address, not the one set in the settings.