The iCamSource can be running on a computer that is connected to a different network as the IP camera as long as you have forwarded the appropriate port in your IP camera's network so that it is able to be connected to. Basically, if you can connect to the camera from your office computer's web browser, you should be able to connect to it using the iCamSource.
Once the camera is being monitored by the iCamSource you should then be able to connect to it using iCam on your iDevice.
As for the network IP camera, it looks like it supports MJPEG video streaming, so it should be compatible.