How to export object with its texture for 3d printing? hopefully, this is a simple noob issue. Yes I have seen that it's been asked again and again and again, and I have tried lots of the solutions but I'm still stuck. 

I have a model that I have applied a texture to and it renders nicely in Blender.



Ideally I want to export this to Shapeways for printing in colour sandstone, or when I eventually get an Mcor Arke, print it on there. So, I have a few options, DAE and X3D for example, these require the texture to be alongside the file in a zip file, and when I upload them, Shapeways says there is a texture (probably because the zip file included a PNG file), but won't render it. When I look in the X3D or DAE file with a text editor, there is no reference I can find to the PNG texture file.

I also tried this post on using the blender render engine, but it still doesn't have a reference to the texture when I export the object.

From when I used to do scanning, PLY seems to have all the image data in the file, so I tried that. Interestingly, Paint 3D recognizes PLY files and renders my bust scan... but, still no model of mine. I thought it may be the mirror modifier, but checking the export attributes, it applies those and includes the UV data, and I applied it manually to test anyway, but no.



Stumped, I continued my search. There was this post about not using nodes, but as I walked through the screenshots, I didn't have the "Mapping" tab that was there, then I did something somewhere and it was there, but it didn't have a UV option for coordinates, when I did the original unwrap I did use the smart option... because I followed a youtube example, so I went back to the beginning of this article, and did the unwrap.... but now I cannot see the material rendered at all in any view. I can't seem to find a walkthrough example of a complex paint job without nodes.

Finally, I found this post. I didn't really understand the explanation, but it did mention baking, which I saw in an option somewhere. So I gave that a pop.



Still nothing. So now I'm out of ideas. Any other ideas much appreciated, but, please bear in mind I still don't know Blender all that well.

If you're interested, here is a zip file with my .blend file and texture.

Any help much appreciated before I lose my mind.
I originally followed this tutorial where it outlines smart unwraping as part of the UV creation process. I started from scratch, and instead of doing the smart unwrap with island spacing, I just did an unwrap (more like one of the posts I looked at) and things now work as expected. The only downside is that some of the geometry has warped into very small triangles on the PNG file, but this isn't (in this case) a big issue.

PLY's still don't embed the data, but that's a problem for another day :)