You can have more than one row of tiles with LoadAnimImage(). The tiles are divided from left to right, top to bottom. You can even separate the rows if you want to, say if each row represents the animation of a different character.
local TileSet:TImage = LoadAnimImage("Tileset.png",32,32,0,16)
'create a tileset from a 128x128 image indexed like so:
'00 01 02 03
'04 05 06 07
'08 09 10 11
'12 13 14 15
Local Player:TImage = LoadAnimImage("Tileset.png",32,32,0,4)
Local Enemy:TImage = LoadAnimImage("Tileset.png",32,32,4,4)
Local NPC:TImage = LoadAnimImage("Tileset.png",32,32,8,4)
Local Dog:TImage = LoadAnimImage("Tileset.png",32,32,12,4)
'This will create 4 sets from the 128x128 image, indexed like so:
'00 01 02 03 <- Accessed from the Player variable
'00 01 02 03 <- Accessed from the Enemy variable
'00 01 02 03 <- accessed from the NPC variable
'00 01 02 03 <- Accessed from the Dog variable