Do you mean that you ran an AC analysis and generated an s-parameter model? My guess is that you probably just didn't run the right type of analysis. What version of HyperLynx are you using here? HyperLynx SI? HyperLynx Analog?
If it's HyperLynx SI, click the Simulation SI menu, then click Run Interactive Simulation (SI Oscilloscope). When you run that simulation, it will give you a voltage/time waveform.