Models appear black even after materials are applied.

I add my own custom material to items that would usually be able to have their textures changed (I'm making a skin for a game), I've done everything I was told to do, make sure the image is a PNG image, restart Unity, reset the model, ETC, but it didn't work. The right hand drop down menu claims that the material is applied, but the model simply appears pitch black.

 

Very stupid question: Are you sure you have a light facing that object?

 

Does light work on your model if you use some builtin materials?
Or if you add default sphere to scene, with your material, does light work on it?

Maybe screenshot would help also.. its black in editor or in build/device?

 

I... Honestly have no idea. I don't speak this scripter/builder lingo and I'm honestly just trying to make a weapon skin. I'm in the editor and there's no scene or anything, it's just all the blank space with the model floating in the middle.
Edit: I found my issue, no there wasn't technically a light source pointed at it, but the last time I tried to place a light source it had a sims-esque prompt pop up with a symbol representing the light, but no actual light.