How to make proper skin files?

Thanks..
I've done all that, but a simple skin I made for the Covet to test is appearing on my parts selector but making no difference.
What'm I doing wrong??

 

Better?

 

yeah, I have,
thanks
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And I just want to thank you generally as well because I've had quite a few queries about various things and you've answered them all in a very friendly way, not just shouting at me because I'm slightly noobish.

 

Agreed, thank you very much Nadeox

 

Been messing around with this for the last week or so (drawing over the lines), and I've noticed that right after I do that, the game only loads in an invisible skin when I choose my skin in the parts selector. Does the game have trouble recognizing the skin if the lines are drawn over quite a bit? The skin, as I said, shows up in the parts selector so I'm pretty sure it has to do with the skin itself. I haven't changed anything else in the files and the skin file name is the same in the material.cs code and as the file itself.

 

Here, it's another test file I made:

 

Okay, thanks for letting me know.