The italicized text for encounters is meant to be read to the players as their characters enter the location in question. Sometimes you’ll need to modify the flavor text. For example, if the flavor text states that “a waxing moon rises, barely visible in the morning air”, and the players have started out in the evening, you’ll need to change that.
In this adventure, nearly every location has flavor text. Some have multiple texts for different times of day and for different perspectives. When you create your own adventures, you’ll usually provide flavor text for key encounters, and notes for the rest. Put in just enough preparation time to make the game more fun for you and your players, and no more.
Note that on the maps of Stelopolis and the castle, the top of the map points east rather than north.