Yes, I'm one of the Photoshop Moderators, along with a few other areas.

Anyway, you can modify the textures all day long, and post the rendered image, you just can't post the product texture maps by themselves.

1. Take your skin texture map into photoshop. That will be your bottom layer.

2. Put your vein map on top of the skin texture map. That will be layer 2.

3. Set vein map to multiply and drop the opacity to 28%.

4. Save as a jpg using a unique file name; like vein_torso_map_001.jpg

5. Apply your new skin map to your character.

6. Take a look at the results, and if needed, go back and adjust the vein map opacity.

7. Re-save the image, but as a different name; like vein_torso_map_002.jpg

8. Apply the new modified texture.

9. Take a look at the results, and if needed adjust again, always saving as a new file. The reason is - Daz doesn't update the texture if you keep saving over the first file, it'll just keep showing you the first version. I don't know why, and maybe there's a way to make it update, but I don't know how. I just keep saving in ascending order as I work on it; 001, 002, 003, and so on. That forces Daz to show you the newest adjusted texture.

The maps you have are super simple because they are the same size and line up perfectly. You should have a finished result in no time.

I'm sure there are a thousand different ways to do it, but this is how I would do it.

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Wolfenshire, Moderator/Community Leader