With the fan fiction series complete, for all intents and purposes, let me explain what started this project.
What eventually became Days of Dissidence started as two video game mods, one for Knights of the Old Republic and another for The Sith Lords. Of the two, the mod for KoTOR was far more fleshed out, had more influence on the fan fiction, and it actually had working content. There were two "versions" of the first game's mod, although only one was actually released.
The overall metastory went something like this: a Sith learner from Alderaan named Zaen Benax is forced to flee after he is accused of a crime he didn't commit. He goes to Dantooine (so he can join the party early as opposed to any sort of plot purpose). He meets up with Revan in the Dantooine fields after bounty hunters kill the family that had been hiding him. When confronted, he challenges Revan at first only to realize that he is outmatched and surrenders. If the player agrees, he joins your party, replacing Juhani, as most KotOR mods tend to do. In the first version of the mod, that was all that happened. You just get a Force-sensitive on the dark side of the scale so a potentially heroic Revan can have a party member that uses Sith powers without penalty (aside from Jolee, of course).
In the second version of the mod, which saw partial release, there was far more content and it was intended to be quite fleshed out. In fact, it may still be on the internet in some form, unfortunately. Zaen (now Raen) still joins on Dantooine in much the same circumstances, except he replaces T3-M4 instead of Juhani. He comes with several unique items, including an armband and suit of armor from Alderaan that would give some nice stat bonuses to whoever wore them. Once he joins your party, several new quests open up for the player. One involved finding a hidden Sith tomb on Korriban and encountering elite Sith troopers being created on Alderaan. Another involved meeting Celsus Djan, a character from the novels, on the Unknown World and doing a sort of endgame sidequest with only you and him. And of course, Raen has much to talk about, and you can influence him either toward the light side or reaffirm his commitment to the dark side depending on Revan's alignment.
Raen's "loyalty" quest, to adopt a concept from the Mass Effect universe, would happen after the Leviathan event at the game's climax. Just before the Ebon Hawk is captured by the Sith, Raen leaves the party and T3-M4 returns so you can still use the droid on the Leviathan. Immediately after Revan and his party escape and Bastila is captured, Revan is informed that Raen left a datapad in the cargo hold for him. When read, Raen explains that he is going back to Alderaan to avenge himself upon the Sith who tried to kill him. From then on, Alderaan appears on the galaxy map, and the player can travel there and help Raen defeat the Sith in their academy. The final boss would have been De'dlay, one of the primary antagonists in the first few novels of the fan fic. Raen stays on Alderaan after the Sith are defeated to avoid any endgame weirdness.
The TSL mod was only in its infancy when the modding project was dropped in favor of the fan fiction. Only the big plot points were set up. Raen would meet the Exile early on, replace a party member (again, probably T3), and follow the Exile on her adventures. This time, he is searching for his older brother, Jaeln, who is the last surviving Sith of Alderaan. Unlike in the first game, the Exile cannot influence Raen, as his beliefs have already been set by Revan. This is in contrast to the rest of the party, who are mostly young Force-sensitives under the Exile's tutelage.
Just before the Battle of Telos, Raen would have left the party again, this time to face Jaeln. This event would have happened in a brief cutscene outside of the player's control, and the player's alignment would determine the victor of their fratricidal feud. If the Exile remains dedicated to the light, Jaeln defeats Raen and flees to the Unknown Regions to find and aid the True Sith. If the Exile becomes a Sith, Raen vanquishes his brother and vows to find Revan and defeat the Exile. Either way, the surviving Benax sibling would either join or fight the player's character in what would have been Knights of the Old Republic 3 (RIP).
Nearly all of the characters in the stories were created for the fan fiction. Some were explicitly created to keep Revan and the other canon characters away from the action. Gaiel Remus, for example, is pretty much a stand-in for Revan's character in Convict's Dawn in terms of the actions he takes and the places he visits. The only characters who had their origins in the mod project were Raen, Jaeln, Celsus, De'dlay, Northeus Ulsan, Preux, and some of the Sith and Republic generals in Knight of Alderaan. Hands of Evening marks the divergence between the mod origins and the written works. Very little from the series' original outline can be seen thereafter.
Ultimately, the modding project was dropped for two reasons. For one, when I started this project, my skill in such things were quite rudimentary. The ideas I had in mind were too lofty and not reasonable. Second, the arrival of The Old Republic pretty much snuffed out any hopes of a third and final mod. Even if it the third game hadn't been an MMORPG, recent Bioware games aren't as modder-friendly as KotOR and TSL, or so I've been told. Mass Effect, for example, is nearly impossible to modify to the extent of KotOR. Could I potentially throw something together just for the first two games? Perhaps. But I think the written works tell the story I wanted to tell just fine.