I finally received the PandaKushio "Smail Adventure Train" from Kato. This is a very easy digitalization as this Kato model is DCC Friendly. You need a EM13 decoder for the motor car, and two FL12 decoders for the tail and head cars. Each of these cars has a small hatch in the bottom part where to slide the decoder in.
I installed also the led lighting kit from kato, reference number 10-214. Here you can see the results of a 10 minutes work: