It is the Desert Colossus' exterior and the surrounding grounds that are shown. The inner confines of the Spirit Temple will assuredly come in to play in another episode, as will other locales. As for when another episode concerning Ganondorf will arrive, I am not sure. There are many projects on my plate right now, dare I say too many, but it will happen eventually; there's too many good ideas there to leave it just like that.
Episode two has been outlined, though I must apologize that it
does not feature Ganondorf. As to whom will take on the role of the main character for the next round, I will let you guess.

The purpose of this series is to explore many of the villains, be it prequels or no, and tell some great stories.
Oh, and thanks, Cheiragonus, for reading and giving thought. I, too, sometimes feel cheated by revealed antagonist's backgrounds, especially when it is done haphazardly. Don't worry, I'm not going to reveal every single detail, as that would just be boring. My goal is not necessarily to tell
why they are evil, or how they became so, but more attune to who they are as a person; making them more flesh and bone than snarl and snap. Does Ganondorf consider himself evil? That is the paramount question I have asked myself. I wish to show perspectives, even though it could be perceived as an undermining factor to the character's aura.
I dunno; I probably just dug myself into an argument I cannot win there.

I just wish to tell a story or two using these great characters. Unfortunately, prequels are generally the only feasible way to do it. :/