Short answers, pulled from the story.
Star Wars: Knights of the Old Republic ran for 50 issues, published monthly by Dark Horse Comics beginning on the 25th of January 2006. A follow-up miniseries, Star Wars: Knights of the Old Republic: War, added five more issues in 2012.
John Jackson Miller wrote all 50 issues of the series. Miller also authored the novels Star Wars: Kenobi, Star Wars: Knight Errant, and Star Wars: A New Dawn, which served as a prequel to the animated series Star Wars Rebels.
The series follows Zayne Carrick, a Padawan at the Jedi Academy on Taris who is framed for the murder of his fellow students by their own Jedi Masters. Forced into life as a fugitive alongside a Snivvian smuggler named Gryph, Zayne spends the series trying to clear his name and expose the secret Jedi covenant responsible for the killings.
The series is set eight years before the first Knights of the Old Republic video game, placing it within the same timeline as the games but in an earlier period marked by the Mandalorian Wars and the aftermath of the Great Sith War.
Lucien Draay is the Jedi Master who trained Zayne Carrick and served as executive officer of a secret covenant of Jedi seers. The son of Barison Draay and Lady Krynda, he organized the massacre of the Padawans after the covenant experienced dark visions of a future Sith Lord wearing a red spacesuit.
Star Wars: Vector was a standalone crossover storyline that ran through four separate Dark Horse series. Knights of the Old Republic contributed issues 25 through 28, forming the first part of the crossover; the story then continued through Dark Times, Rebellion, and Legacy.