1.
As Kalphiter said:
Server asks client if they have it, via commandToClient
Client responds when clientcmd is called, sending a commandToServer, possibly with a version variable as well
Server acknowledges that the client has the mod from the serverCmd
2.
Stored on the client object, in no particular order:
.packColor = 4 values from 0 to 1, separated with spaces, eg. 1 1 1 1 for white.
.lleg and .rleg = 0 or 1. 0 for normal foot, 1 for peg leg.
.rarmColor and .larmColor = see packColor
.chest = 0 or 1, 0 for male, 1 for female, in other words, 0 is the flat sides, 1 is the curves.
.hipColor = see packColor
.accent = head accessory, each number is a different one, not sure which is which.
.hip = 0 or 1, 0 is pants, 1 is skirt, feet color determine trim color of skirt
.rHand and .lHand = 0 or 1, 0 is hand, 1 is hook
chestColor = see packColor
decalName = name of the decal image
secondPack = shoulder accesory, not sure which is which.
.rarm and .larm = 0 or 1, 0 is normal shoulders, 1 is pointed
.lhandcolor and .rhandcolor = see packColor
faceName = name of the face image
.rlegcolor and llegcolor = feet/skirt trim color, see packColor
.secondpackcolor = see packColor
.pack = back accessory. Dunno which number is which.
.hat = head accessory, ^^^
.hatcolor = see packColor
.lanname = Lan name (doesn't update when player changes, pointless for online play unless you somehow stumble on an alt)
.clanprefix = first clan tag (doesn't update when player changes, can be changed)
.clansuffix = second clan tag, also doesn't update
I think I got all of them.
