Sorry, I'd been meaning to get to this earlier and I had decided to make changes to some stuff I'd prepared for the next arm of the adventure (you guys are too strong and aren't in nearly enough danger of dying). Through sheer laziness, I still haven't gotten to that. But that's no reason to hold this up...
Tomas gets Revaethan and Carrow to closely examine the mentions of Khaligri. They come to the following findings...
-Other than Orm and a "candidate" whose name is either encoded or substituted with a title, Khaligri is the only person the author bothers to focus on and repeatedly call by name. And for those other two individuals, mentions are usually in the context of magic rituals (the author appears to be trying to emulate Orm's magic and follow in his footsteps, and the "candidate" would seem to be a sacrificial victim for some ghastly ritual). Mentions of Khaligri are generally non-magical in nature, with the author extolling her beauty or just repeatedly inserting her name in the middle of other mundane notes.
-Dark elves are known to be able to use magic to lull others and bend them to their will. While Tomas doesn't have direct experience with this, he has heard of the phenomenon and strongly suspects that Khaligri was using her magic to manipulate the author of this book.
-Tomas gathers that some of the magic here is related to the Loren forest and even more specifically to the seasons here, which are important. He notices that much of the magic isn't really that complex and that someone versed in the magic of Loren would easily be able to interpret it, but he seems to be missing key information to put everything together. Still, he can tell that part of the author's goal was to ascertain timing details, that the rituals he wanted to perform had to be done in the right order and at certain times and places. The whole thing was probably intended to disrupt some natural cycle.
-Most of the magic described here is experimental, with a visible record of trial and error. The author may not have been a novice mage, but was clearly out of his element. In contrast, the rituals attributed to Orm are painstaking copies of something far more elaborate and ancient. Tomas gathers that Orm is/was a powerful necromancer.
-Although Tomas is not absolutely certain, he thinks that he has grasped the author's goal with all of this magic. Everything here was preparation for extracting heartwood from certain (presumably very important) trees in the Loren forest, grinding the wood up into chips and despositing them into a cursed basin, cutting out the heart from a victim (known as the "candidate" or "subject"), and burning the organ in the basin, finally breathing in the resulting smoke and channeling the Witch King (leader of the dark elves), presumably cursing the entire forest, stealing its magic, and giving the performer of the ritual massive power.