Starsgem CAD help

[pixiepie1987]

Hi all,
I got this CAD from Starsgem and am a little confused. See my inspiration photos below and the CAD.

What’s confusing me is:
- will the rings actually sit flush together? How do I get across how to fix this?
- the 2.9mm measurement.. I certainly don’t want it that wide or that big Of a size difference between the rings (2.9 vs 2.45 if I’m reading right)
- prongs look like claws but I just wanted round button type prongs

Any advice would be great - my first time doing this!

 

[lovedogs]

I don't think it will sit flush bc of the donut, but I'm not a CAD expert, so don't take my word for it!