Chateau Sylaire is supposed to be the ancient mansion of a gazillion high level mages; there are seven mages of double-digit levels as NPCs, including two 20th-level mages...and more than a few other mid-level ones. Does Sylaire live up to this promised wackiness?
Well, no. It winds up feeling more like a traditional manor with a few "fun" rooms thrown in. The traditional manor bit could be a good idea; the dominant forces perhaps ought to be the wacky NPCs, with the surroundings playing straight man. Still, you can't help but want to see some goddamn fun house stuff - Chateau Sylaire would be the place to put it in!
The second floor has the Glory Windows, which show strange and vaguely prophetic illusions at sunrise. It's also got a flying carriage house, a room built for family members using fly spells to come in and dry off. Not exciting, but it fits the manse's intended tone really well so it gets a half point. Four pages
The dungeon has a trapped and staked vampire from not-Transylvania (meh), a flesh golem on a hamster wheel pumping water for the house (good!), a magic door to Clark Ashton Smith's Averoigne (hell yes!)...and some boring rooms after that. Golem construction and summoning otherplanar critters shouldn't be boring. At least the d'Ambrevilles have some zombie servants, because c'mon man, they're insane wizards, they should get something fun.
The other thing here is that these set up a "normal" so that they can get turned into scary mode later in the module. That's fair enough, but c'mon. The combo of Zelazny Amberites and Clark Ashton Smith Averoigne deserves something grander and weirder, even as a baseline.