mapping K2, basic newb to midi question.

Decided that im going to try and make a custom mapping for my K2. Ive been playing with traktor for 4 years now but mostly im a cdj guy. Point being that ive never got deep into mapping. Im running TP2 and last evening I managed to map some simple commands, cue, play, next, prev, toggle browse and so on. I had trouble mapping sync as there are three or four sync options and as far as I can see not just one "sync" as appears in Tpro. Im sure im missing something simple. ANy ideas?

Next im trying to get my head around modifiers, my basic understanding of them is that I can use them to program say a "shift" button then use it to ad an extra function to another button providing shift is being held.

An idea I have in regards to browse/select and deck assign is to have one of my rotary push button encoders mapped to switch to browse view when roary action given, then browse list, press encoder to select track. Once track is selected I then want to be able to use same rotary action to shift deck focus for assigning to desired deck. The browser view I noticed last evening has the mini decks showing above the browser... is this possible?

to "if possible" make it clearer.

first turn of encoder one incriment = browser appears
further turning = scrolls
press encoder = select track
further turning = scrolls deck focus for deck assignment (is this possible)
press encoder = select deck and return to deck view

I guess I will need to add a modifier shift acton to close browser. Say "shift + press encoder" to return to decks.

its all about as clear as mud to be, but its also sparked my inner geek.... im actually looking foward to finishing shift so I can punish myself with my seemingly hopless situation in understanding midi mapping.