1. http://skyrimming.com/wp-content/uploads/2011/12/FileSR-book-Oghma_Infinium_1.jpg from the Oghma Infinium seems to depict the cosmos, but it's different from the layout of the Imperial City. This one has 9 or 10 spokes, and smaller circles within. Did the Ayleids get some details wrong? Is the Imperial City unfinished?

2. From what I understand, the 36 Lessons of Vivec, and the concepts of Amaranth and CHIM, describe the Elder Scrolls universe as being a video game, and that if a character were to realize this, they would in effect have access to the command console, right? What characters have realized this so far?

3. Do you think that the Khajiit and Argonians came from Akavir? I only say this because the other races/proto-races came to Tamriel from lands around it. Aldmer from the South, Redguards from the West, and Nedes from the North, so maybe originally there was a pattern and a race was supposed to come from the East. And Akavir also has tiger and snake people.

Dunno about number 1. As for 2.. I don't think it's actually intended to be breaking the fourth wall. It's the deeper purpose/lore of the metaphysics/theology of TES. As for what characters have achieved.. do you mean player characters? Or like, Vivec and Tiber Septim? As for 3.. no. Khajiit are supposedly elves changed by Azura and Argonian are from the Hist. I think it's more likely the Akaviri races came from Tamriel.

1. I already noticed as well. The reason for the IC only having 6 spokes may simply be a technical one. Adding 2 or 3 more districts would have required a considerable increase of diameter. If one wants to search for a lore reason, though, you can look at the elven pantheon. For example, their version of the time dragon is not a spoke of the wheel but resides in Aetherius. So, a screw up because of their world view? Did the dragonfires add that missing spoke, actually turning White-Gold functional? Which other spoke would be missing?

2. That's one way to see it. The more in-world concept though, is that reality is the dream of a sleeping godhead and everyone is just a product of that dream. CHIM is to realize this and still hold on to your individuality, essentially becoming a lucid dreamer who can change the dream at will. Amaranth is to leave the dream and become a dreamer yourself.

Right now, there are two known CHIMsters, Tiber Septim and Vivec. Tiber used it to change Cyrodiil from jungle to forest ("I breathe, in royal splendor, and change this land...")

Vivec is known to have it only after the events of Morrowind. When exactly he got it, and if he already had it as a god, is unknown.

There is one person/ concept who became Amaranth, but noone figed out wno it is, yet.

3. Khajiit, according to their own creation myth, are relatives of the Bosmer, who, as pointed out above, where changed by Azura. Argonians are supposedly common lizards who were made sentient by the Hist. The Hist themselves are coming from a plane of the Hist that is floating around Oblivion, which seems to be a fragment of a previous kalpa.