Does Tyto endorse this?

Yes! I have gotten confirmation to take payment for the files.

What are the internal parts for?

In order to make this helmet more wearable, comfortable and to bring it closer inline with Tytos vision in the comics a host of electronics and hardware have been added.

Are there build instructions?

Yes! Both instructions and a build blog are currently being assembled.

Do the files have any issues?

There are some general small issues with the STL files but nothing that should make the 3D printing unecessarily hard. It is well optimized for a standard build volume of 256x256x300