THE MAIN BUTTON here is the Load Button, which I mapped to Load, Loop and Play, coupled with a Sync Function  and a Keylock On Function.

I did it because a lot of times, and more when you're improvising a live set, the last thing you want is to loose time, syncing, pressing play and setting loops (as far as almost all the Digital DJs don't mix long intro tracks as Trance, for example), and even you cannot forget to key lock your tracks, if you're mixing very different tempos.

Syncing is essential if you're going to load next track to be in time with the current or master track and if you're going to loop a 116 BPM track with a 124 or higher, the last thing you'd like is to have a chipmunk voice in you're synced tracks.

The Other Important "one Buttons" are Play and Sync.

I Mapped the Play Button with a "Set as Master Tempo" function, because some times you will reset tempo on the next track and you can't do it in the right time because you forgot to set the new track as Master.

That took me to map a "Reset Tempo" button, because the X1 Doesn't have it mapped by default and the only thing you can do is loosing time pressing shift+Out or moving the Pitch Adj in your Turntable/CDJ.

I hope all of this tricks really be helpful for Djs using loops and needing syncing, looping, setting master and resetting tempos.

That's a one button mapping, but doesn't combine functions, just improve one: the Beat Jump: Instead of jumping one beat, will jump the exact number of beats set in the loop size.

Aditionally, not one button mappings but not for that less important I did some improvements in critical parts of the X1:

The Loop Encoder has two new functions:

Pushing it it will set loop as normally and turning it will change the loop size. But Pressing Shift, Pushing it will Play/Pause the Corresponding deck (That has in mind when you're in Hotcue Mode or just when you don't want to set that decks as Master) and turning the encoder will move the loop in the loop size as in the S4 secondary encoder, and not moving just one beat, only when Loop is active. When you have no loop, you can jump the exact number of beats pushing <Beat or Beat> as explained upper.

The On FX buttons act as On when you're in Advanced Mode, in Group mode doesn't work. With Shift they Change The FX mode.

The "1" Button will Turn on the corresponding effect when you're in Group mode or however it acts in Advanced mode; and plus shift it will turn on Flux Mode in the Corresponding Deck.

The "2" Button will Turn on the corresponding effect when you're in Group mode or however it acts in Advanced mode; and plus Shift it will assign the four FX units to the corresponding deck.

The "3" Button will Turn on the corresponding effect when you're in Group mode or however it acts in Advanced mode.

All the knobs work Normally, but plus Shift will Select Effects. The D/W Knob selects effect when you're in advanced mode. The "1", "2" and "3" knobs will change the Effect in their corresponding numbers. 

I hope it be useful for all of you, because I really did it thinking in very useful Functions :)