The backstory was interesting. I found some errors in it though and it is in need of some editing.
Page 5, Introduction: "You can choose from ten civilizations"
Should be twelve.
page 9: "An interstellar war unfolded between the Human-led Coalition, which included the Altarians, Torians, and Arceans, and the Drengin Alliance, which included the Drengin Empire, the Yor, the Drath, and the Thalan. Two civilizations, the Korx and the Iconians, remained neutral."
Incorrect. The Human-led Coalition also included the Altarians, Torians, Arceans and Iconians. The Drengin Alliance also included the Yor. Three civilizations, Korx, Drath and the Thalan, remained neutral throughout the war.
page 28, backstory: "In the same way that a map of the Earth becomes distorted when it is flat, the map of the galaxy becomes distorted when made flat."
page 87-91, The Backstory: Editing needed.
My suggestion is to get someone good at editing to go through the whole manual. And remove all the "Regarding the...".