Have you (or are you) used/using the transaction viewer? I don't have any X-10 devices, but that should let you see whether its getting a command (which would tell you the schedule is working)
Port Spy would let you see whether Premise is sending the command.
In schedule, once you have the object and schedule in place, you can hit play. Using the port spy, you should see the command being sent.
One other thing to check (and port spy will capture this for you) is if you have the schedule set, and you hit play, if the timeframe you are troubleshooting out of the schedule time, you may miss the command being sent...