OK, just to complete the answer on the primary question in this thread:
NO, if a unit isn't choosen and AI is switched off, also the code in it's init field disappears.
Possible solutions are:
What nomesine already suggested: put it into each unit's init field
or: create a trigger covering the whole group - activation: side of the group/present/once
condition: this
onActivation: gr1 = group thislist select 0
Another way is also:
name each individual of the group like: g1,g2,g2...g12
and in init.sqs you could do following:
grp_array = []
"if (alive _x) then {grp_array = grp_array + [_x]}" foreach [g1,g2,g3,g4,g5,g6,g7,g8,g9,g10,g11,g12]
gr1 = group grp_array select 0
Off course there are way more methods to do that and i don't want sit on your head to take this or that, but
the 3 i mentioned work for sure and you should take the one which you most prefer.
~S~ CD