Heres a better Idea of the process that I did when creating my recent 3d render of an Isaac sculpt. This is the first time I had properly integrated 2 seperate 3d software to create a rendered image.

For the main sculpt itself I modeled and textured the character in sculptris which took around 30 minutes to do. The model was then exported as an OBJ file and a texture map was created sepreatley as with sculprtis when you export a sculpt the textures are not on the model.

 incase you're curious this is how big of a mess a Uv map is from sculptris

The model was then imported into blender where the textures were added again and a basic scene was set up. The most challenging part was figuring out how to create light rays using a default spot light. Through trial and error eventually I achieved the effect by creating a ciylinder and parenting it to a light with transparent texture map.

And after an agonising wait for the thing to render, the final result