The problem with Atlas switches was present with the original VL Challenger too. Plus, for those who can remember back that far, those engines shipped with a board defect that meant the battery, if installed, would continue to discharge and power the rear tender lights after the engine was shut down. The boards had to be returned to Lionel for re-programming if you wanted to use a battery without it constantly running down.
I think it was in that context that Lionel said they could not make engines that run flawlessly on every variation of track brand and in particular Atlas. I understand that position. I used to use Atlas but switched back to tubular track.
BTW, the new VL Challenger manual is up on Lionel's website and in common with every Lionel Legacy steam engine I have got from the VL BB going forward, there is no option to install a battery in the tender any more.
