ah, the crack explains the stars. probably no amount of cleaning is gonna remove that. it looks kinda cool but you'll find sometimes it breaks the image when there's too much contrast.

regular microfibre cloths are gold for optics in general. polished surfaces, glass, plastic... don't even need any solvent very often. 

 Yup. It worked out in this case, and I have a new cover to stick on. I just forget.

I love microfiber, I just don't usually have one on me.