Questions about textures

[o0DemonBoy0o]

Hey guys, I wanted to start submitting models here again and had a few questions. 

1. What formats are allowed again? I currently have been ripping everything in obj, dae, and dds formats. Obj and dae should be fine, but I wasn't too sure about dds textures. What would be the best format to use if I can't use dds?

2. I have mask textures that look like this

I'm thinking it would be best to just have them as separate black and white images rather than just one image like this?

3. I have some other textures like this

I already know that the red channel is a spec map, and blue is an Illumination map, but what about green?
Here is a link to the original dds if needed.
https://www.dropbox.com/s/53j95lek9zxmsv...e.dds?dl=0

4. Not really a question but a request.
Can someone remove the Racthet & Clank: A Crack in Time models I have uploaded now? I have far better ones ripped with correct textures and UVs.

[Mystie]

.PNG is the only format allowed for textures, as far as I know.

As for the other questions, I don't know too much about them, sorry.

[o0DemonBoy0o]

So only .PNG then? Alright then. I think I got the answer to my 3rd question. It seems to be a gloss map.

Would sill like some confirmation on the mask map. This is my first time messing with them.

[TGE]

masks like those are usually shader-specific
it'd be wise to save the channels as seperate PNGs