Lyne

Actually there can be no difference between a p5/p6 mat pz2 and a mt5 or mc6 set. Just depends on how the maker set them up really.  Generally mc6 or mt5 files have more Material room nodes and such used since they dont need to be p4 compatible, but not always.

Generally  though pz2 MAT files are for poser 4, pp and p5.  These files may or may not have advanced material shader room options.

An mt5 is a poser 5 material (or shader) you can apply it to anything and it will apply its material settings. It only works on one material at a time, and can contain both node based effects and image based effects. Some materials are for applying specific imagemaps, some for shader effects such as water or stone.

An mc6 file is a Material Collection file and you can make them with Poser6. This is a set of material settings set for specific materials (for a certain model) rather than a one shot like an mt5.  The mc6 is generally set for just one model and will change all the materials at once. Since you can make and adjust them in poser, this takes a lot of work out of making mats. Thankfully. 

You can also take any existing MATpose.pz2 and turn it into a mc6 file by changing the file suffix to mc6 and putting in in the Materials folder. It will still apply the same settings, but you wont have to chase it down in the Pose folder.  I've already corralled all my MAT pose files into the materials folder so I can actually see what I ahve in the Poser folder for the first time in ages :)

I havent tried turning an mc6 into a pz2 yet .. so I dont know what would happen if you try that.

If you buy the most excellent ShaderSpider script from Poseworks you can make all these material settings in poser at once. I've found it very helpful in setting up all the materials I need for my products wihtout all the tedious text editing and file renaming.

ps Lyne you definately want to play with the displacement and bump and specularity settings in the shader room. I had entirely too much fun setting up mermaid tails with poser6... I'd like to see what you can do with some of your great animal textures :)

Lyrra