Make *.exe build use actual images?

Is it possible to make *.exe build use actual images (*.png, *.jpg) instead of sharedassets0.assets files? What do I need this for? I already have a complete set of graphics for my game but I want my graphic artist to create another theme. So it would be great for him to have a preview of what he created. And since he can’t use Unity I thought I could make an *.exe build that’s using regular images files - therefore whenever graphic artist changes anything with graphics - they can easily check out the result.

Unless you have better ideas how to let the graphic artist preview his work?

Use WWW.texture.