I don't expect that this will lead to errata, but I want to see what the range of opinion is like.
The goal is to use MuAn to turn all of the woolen clothes that a person (or people) is wearing into silk. (No requisites required. Note that linen would require a Herbam requisite.) Range is Touch. The question is whether it can be done with a single spell, and if so how. More than one option may be possible.
One Person
A) Individual, and you only need to touch the person.
B) Individual, but you have to touch at least one of the clothes.
C) Individual, and you only need to touch the person, but only if they aren't wearing linen underwear.
D) Individual, but you have to touch at least one of the clothes, and only if they aren't wearing linen underwear.
E) Group, and you only need to touch the person.
F) Group, but you have to touch at least one of the clothes.
H) E, but only if they aren't wearing linen underwear.
I) F, and only if they aren't wearing linen underwear.
J) It can't be done. The clothes worn by a person do not constitute a Group of clothes.
Six people in a Group. (Assume the caster is a magic item, and ignore the question of whether it is part of the group.)
K) Group, and you only need to touch one of the people.
L) Group, but you need to touch one of the clothes.
M) K, but only without linen underwear.
N) L, but only without linen underwear.
O) It cannot be done, because the clothes worn by a Group of people do not count as a Group of clothes, although the clothes worn by one individual do.
P) It cannot be done, because the clothes worn by a person do not constitute a Group of clothes.
A number of people in a room.
Q) Room, and you only need to touch the wall of the room.
R) Room, and you only need to touch the wall of the room, but it will change all wool in the room to silk, not just the clothes.
S) It can't be done. There are non-Animal targets in the Room, so a spell with that Target fails, and no other single Target covers everyone.