BOAC:
As eckhard above - the FMC simply follows a ground track - the track of a still air hold. It makes NO allowance for wind effect in the turns other than bank angle variations. IF you ever fly an LNAV hold with an (Icelandic
) severe wind across you will see 'fly-through' at one end because the bank angle limitation will not hack the turn.
Depends upon the sophistication of the FMS. The current specifications call for calculating the pattern to be flown predicated on the known wind direction and velocity at pattern entry. In strong wind conditions the pattern projected on the moving map should look like an elongated, misshaped egg.