Most images used for commercial Poser / D|S product textures are jpg images.

Can you post a link to the product you have and show what you are trying to do with it? And maybe a shot of what you have so far, with your Mat Room setting?

I may not be able to help you myself, but someone surely will if we can see your image, and what you are doing "wrong", if I may put it that way.

Izi

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)