You are pretty much on track up to this point. From a legal standpoint, Inventables cannot host links to files of copyrighted or trademarked material.
I tried to be very specific in my posts above. No one is suggesting that people cannot make things for their own use and post pictures of their work.
Some people think sharing files is a grey area. It is not.
Think of .mp3 and movies. Even if you did the work and recorded them, they are a facsimile.
I’m not trying to be a jerk here. I’m not giving an opinion or blowing hot air.