Adding textures (newbie and using 1.4.1)

[micheus]

Hi psycholinguist, welcome to Wings3d and our community.

I can't say nothing about the file format restriction, since I don't have a Mac, but about the Refresh be absent that is happen because you are using a Internal image - it needs to be a external in order Wings3d knows that can reload it. (note the menu option Make External)

If you already have a external texture, then you can use the File->Load Image and then in the Outline window select it and drag over the material. When you release the mouse button you will be prompted about the texture type and you should choose Diffuse. After that, you can delete the old internal one.