TEXTURE0_ONLY it is value for effectPreset it is used in Marmalade material files (*.mtl) from “data” folder

effectPreset "TEXTURE0_ONLY"

When I searched there was only one page in Internet. It was on Marmalade forum.

Here is second page ))

If you set that flag then second texture (when provided) will be ignored.

It could be used if you defined custom shader and you need second texture for shader.