Sort An Array In VBA Memory

two parts:

1.
The following is the VBA version of what i've been using:

Range("A1:J1000").Sort Key1:=Range("D2"), Order1:=xlAscending, Key2:= _
Range("E2"), Order2:=xlAscending, Key3:=Range("F2"), Order3:=xlDescending _
, Header:=xlGuess, OrderCustom:=1, MatchCase:=False, Orientation:= _
xlTopToBottom, DataOption1:=xlSortNormal, DataOption2:=xlSortNormal, _
DataOption3:=xlSortNormal
now arrays are bigger than 1000 rows>> even bigger than 65536.

Such an array is stored in "arrBIG" and dimed as (1 to 10, 1 to 100000). The goal is to sort it by the 4'th, then 5th then 6th values in the first dimension - the one that is 1 to 10 - i call this the column.

arrBIG.Sort Key1:=4, Order1:=xlAscending, Key2:= _
5, Order2:=xlAscending, Key3:=6, Order3:=xlDescending _.................