The Grand Apparatus is a Mech

[Yuripetes]

I have a theory that the Grand Apparatus is actually the Cosmere, and that it is a Mata Nui (Bionicle)- style robot. Canticle is the power source. Other planets were made by the Shards, which can be considered parts of the mechs consciousness. 

The Cosmere is Adonalsium.

Edited March 30 by Yuripetes
Clarification

[Frustration]

Have you read Isles of the Emberdark?

[Yuripetes]

Not yet

[Frustration]

Well, Isles will explain what the Grand Apparatus is