If you want to make preview, even if you dont have 512 textures, then simply copy all the textures to uke folder in toirbash directory (toribash/custom/uke) in .tga format. After that open toribash and start single player. All the textures will be on uke.
Now about the texture. It is pretty cool but there are some problems with mapping.
First of all of course the top, you need to fix it. Another problem is the face part, everything seems blured, try to redraw it, but this time try to sharpen the edges as much as possible. Another thing that I don't like is the back. I haven't seen much dragons in my life, but I'm sure that the back of dragons head looks different from what you have drawn, try to redraw it adding some scales or I don't know... be creative.
For now I rate it 6/10
I will rate the set, if you make a preview.