Hi Greg, you are correct there is no chuff trigger wire. The plan is in the next version will activate the purple wire for the chuff input. This will be a software download.
Also the steam sounds will get a upgrade to the UTL files. Most of the diesel and horns have been updated.
The LM-3S-G loco module is rate at 6 amps continuous and 8 amp stall current. The audio amp is rated at 13 watts into 4 ohms and 7.4 watts into 8 ohms. It can be very loud!!