Trigger that remembers the favourite before match starts

Hi
That information is available in variables in-play:
last_order is the order of the selection just before the off
last_last_traded is selections last traded price before the off 
last_backp is selections last back price before the off 
last_layp is selections last lay price before the off 

example trigger
set user variable, name: fav, value: "sel_name"   
set user variable, name: favprice, value: last_last_traded
first matching selection
status: in-play
once per market
condition: selections trigger expression last_order is equal to 1

then in your CS trigger you can use the values of fav and favprice