The first in each group in the ImgList is always the diffuse it seems -- I can check the rest in a couple of hours if Snaitf doesn't beat me to it =)
There are no left and right corners as far as I've seen -- they seem to be mirrored? (If you look at the brick wall screenshot I posted in your wrapper thread at mts, the mirroring looks quite obvious on that one) I'm not sure how the plain (non-corner) piece is being referenced right now (maybe we already know and I just don't remember .. was kind of late yesterday =P)
Also
ok, so CWAL points to MATD which points to the bump (which s4pe calls normal)
There seems to be a wrong label in the MATD? I looked at the file Snaitf had digged up there and that looked very much like a bump, not a normal. Or are there any normal maps in TS4 that are not disco-coloured?