Instructions for Material Upload

Saving Material for Upload.

1. Start a new document (not the Preview scene use). Material file must be clean. No objects, no layers. Title of material have to be understandable.

2. If you use textures, make sure that those of (commercial) rights are free and you have permission to pass, if they are not your own.
There should be no path or catalog available in the window, only the file name.

3. You always save material file with File › Save Project with Assets... option. The Title of Folder/File is the Title of Material.

4. Make archive of Material Folder.
For example if you don`t use any textures, archive will contain folder with one material file and Preview Render Image, if you use textures, archive will contain folder with material file and Preview Render Image and also folder tex (with textures in it).
Acceptable extension of archive: ZIP or RAR.

Rendering Material Preview Image

1. Download and extract Material Preview Scene. Open it.
2. Add your material to scene, check that all textures are loaded correctly and no missing textures.
3. Assign material to object: Select the object Shader V1.1 ball and draw your material in the Attributes window (Material)

4. Don`t change any settings or image resolution (800 x 800 pixel)
5. Save Image like JPG file.

And now, upload your Material

The Material Preview Scene was kindly provided by the author (Paulo). In addition to this here the link to the forum post.