How Do I Convert BLP to PNG and Back Without Breaking the Texture?

[ruethgar]

I wanted to change two of the skin colors for the troll PC. This is for 3.3.5a. I extracted the blp skin files from common.mpq and have tried three different BLP converters, but after converting back and forth from either PNG or TGA, the texture breaks and I end up with a lime green troll. I was using the TrollFemaleSkin00_0100 as a base and left that file alone apart from copying and renaming it. That texture was unbroken so I know it is an issue with the conversion process and not the pathing but I'm at a loss as how to proceed. It there any help this form can offer?

[brotalnia]

This one works for me -> BLP2PNG : Developer Utilities : World of Warcraft AddOns

To edit the PNG i use Paint.Net.

[ruethgar]

That was one of the three I used. Even without editing it. Just converting BLP to PNG and back, it breaks the textures.

I'm wondering if it is some effect of the character skins themselves as I can edit single skinned creatures just fine(took out that awful blue on the RaptorSkinRed).

[modpat]

I found it sometimes breaks if the BLP has an alpha channel. Try saving your skins as opaque/no alpha channel.
Capture.PNG
I'm using a photoshop plugin, but it should work with any tool.

[ruethgar]

Re-extracted the skins unedited and just threw them into an MPQ with switched names to verify that it was working(it was). But even when getting the BLP plugin for CS4 starting anew and marking as opaque, the skins still broke. Thank you for trying to help. Wish I could just figure this out.