The mod "sort of" works, meaning having modded curved lane changers 1) keeps the power base from going into safe mode, and 2) the lane changer paddles function as designed. The problem with the the traditional mod with the ARC Pro is that the rails in the cross over section of the curve act as if they're "dead". Since the mod has the right hand rail running off of lane 2 power, and the left hand rail running off of lane 1 power, the design of the ARC Pro powerbase doesn't pass the data through as done with the old 6-car power base, so the car loses it's data feed, and "stalls" on the cross over.
Instead of trying to work out a more extensive mod (as I've seen discussed in other online posts), I'm replacing my 2 curved lane changers with standard curves, and I'm adding straight lane changers immediately ahead of those curves. This is a more straightforward fix, albeit expensive, but in the long run I think it's the best solution (after my wallet recovers).