With this mapping you can now control 4 decks in traktor and you can use it in RekordboxDJ, you just have to choose the right folder on the DDJ400_TRAKTOR.rar and follow the instructions that are in the Youtube Video. This is not an upgrade for my previous mapping, this is a different version, for some people doesn't have any point control 4 decks with a 2 channel unit but for some people (like me) this could be extremely useful. In this version flux mode it's no longer available and most of the time you will have no visibility on the global section (The  4 decks will be at advanced mode most of the time) but it definitly have certain improvements like a corrected vinyl mode and a best use for the pads.