We'll need to know more about what you have done. What is the address...for one? If it is considered a long or an extended address, you will have to set CV 29 to either 38 or 34, depending on whether you want to have the decoder sensitive to DC current.
Some decoders need a resistor or a booster to get the right current to the decoder if you are using a programming track and Paged Mode.
Program it on the main line using Ops mode programming. There's no readback on the main but results are easy enough to see.
There's also the undocumented "Blast mode" on the Zephyr. Blast mode turns the Zepyr's programming out put into a full current broadcast programmer. When in Blast mode, Zephyr will program everything on the track so you have to remove all but the engine you are programming before using it.
To activate Blast mode, C lose Op Switch 7. When finished programming, you must T hrow Op Switch 7 to deactivate it. (that's why its not documented)
Martin Myers