AnalogChannel works as intended - Which probably means you aren't initializing it right or you're hooking it up wrong. If you have it hooked into slot 1 at port X, you should have something along the lines of
AnalogChannel* ultrasonic = new AnalogChannel(1, X);
Then, you just do ultrasonic->GetVoltage(); to return the voltage back from it.
As a reference,
http://maxbotix.com/products/LV.htm
I don't recall the exact model, but make sure pin 1 is grounded to the analog input module (0v, or -, depending on the markings on the analog input module), pin 2 is connected to the +5V on the analog input module, and pin 5, the voltage output (not any of the other pins), is connected to the sensor pin on the analog module.