TMCC Base 1L/Cab 1L

First  off, you do not program the transformer and the locomotive at the same time. Generally speaking, one and only one device should be in program mode at a time.

To me, it almost sounds like you want the ZW-L in 4 channel and conventional mode and you simply just lift the track handle to ~18VAC and let the CAB 1L speak to the locomotives directly... Once you get that working, we can graduate on to switching the ZW-L to command mode and letting you use the CAB 1L to remotely control the 4 channel throttle levers on the ZW-L.

The BASE1L/CAB1L and the Legacy #990 command system have exactly the same track output signal driver circuitry, either of them will output the same level of TMCC track signal.

I agree with the previous post, stop screwing around programming the transformer!  Set the track voltage to 18 volts and use the CAB1L remote to operate the locomotives.  This should be a no-brainer, don't make it more complicated than it is.  For command/only operation, I actually just use the Lionel Powerhouse 180 bricks, no mystery, if the switch is on, there is 18 volts on the track.

To gunrunnerjohn and bmoran4-  Thank you for you input!  Taking your points into account, and the frustration I have had with understanding how to make command control work for me, I have opted to run in Conventional mode instead. The trains run flawlessly, so I know my track work and wiring are solid.  I have spent hours reading the manuals that come with the individual products, as well as trying to install the system over and over again to no effect.  I know what the equipment is supposed to do, but it just isn't happening for me.  And I am OK with that because operating the ZWL throttles is fun in itself.  So- thank you again for your time and responses.

DenverAnnie

"I programmed (I think so anyway) two Legacy locomotives, being sure to have the Program switches turned on, on both the transformer and the locomotives".

You must program each locomotive individually giving it a unique ID.  Two of the digits on the locomotive's cab are what I use for the ID.  Same goes for each of the 4 channels of the ZWL. 

As bmoran4 noted, sounds like your ZWL is now programmed with the same Eng/Tr # as the locomotive(s).   In command operation, the ZWL needs to be commanded (with the Cab1L) to ramp up the track voltage from whatever the minimum.  When you powered up after programming, the ZWL was supplying a minimum voltage to the track.  The Legacy locos need 14 to 18v to run AND a programmed ID that is discrete from any of the ZWL channels.

Put the ZWL into conventional mode, connect the Base1L,  and follow the instructions to individually program each locomotive.

If you have conventional locomotives, then you can control them using the Cab1L.  This is why the ZWL has a command mode.  Follow the instruction to program each of the ZWL's channels.  Give each channel a unique ID.   Consult the manual to learn how to use the Cab1L to control voltage - there are button sequences you can use to quickly set the track voltage to 18v for command operation of Legacy/TMCC locos.

Hello Tracker John,    Your explanation of what happened in my efforts to program my engines makes some sense.  I have had a great deal of difficulty deciphering  the programming instructions contained in the various manuals. I've spent hours trying to get the locomotives to respond to the CAB 1L to no avail. I must confess that I do have a reading comprehension issue, so that definitely comes into play here.  In frustration yesterday I disconnected the CAB 1 base, and flipped the switch to conventional running on the ZWL. My Legacy locomotives came roaring to life. My careful track work and wiring were validated by trouble free running. And I had such fun working the throttles of the ZWL. I have good visibility of the entire layout despite the stationary position of the transformer, so I won't miss the use of a handheld controller. I'm going to be very happy to just keep things simple by sticking with conventional operations.  I do want to thank you for your thoughts though!  

DenverAnnie