It's taken more time to write about this reconstruction, because it is perhaps a more sensitive subject, and more complex, than any I have written before about Mormonism or Christianity, yes, even more so than Jesus or Joseph Smith (which might be an indication that something is off-kilter). The Salt Lake City based Latter-day Saints take the Book of Mormon very seriously as a holy text, as scripture revealed by God, similar to the Bible, and perhaps even more important than the Bible. The Book of Mormon is one thing that makes them unique, their own testament of the divinity of "Jesus Christ," which they believe is also evidence of the unique prophethood of Joseph Smith and the divinity of the church he organized as God's "true church." But I think the truth may be much more nuanced.
The God we are referring to is often known in Mormonism (and more generally in Christianity) as "God the Father," "Heavenly Father," or just "the Father."
I will begin to offer a reconstruction of the Mormon narrative, which also applies in many ways to Christianity in general.