Well, I couldn't figure out how to make the keys work - I got the sense that I needed to collect all of them, and in some way use them to open the final door, but neither "unlock" nor "use" seemed to work, and they failed in ways which seemed like the standard Inform "this command isn't implemented on this thing" fashion, rather than a "this would work except you lack a prerequisite" way.
I also could never figure out the use of the "seizethehorny" custom command, which seemed to fail or succeed depending on the relevant stat, but never to do anything useful - sort of like when you say "xyzzy" at the wrong time in Adventure: it clearly does a thing when used in the right context, but outside that context it quietly does not a thing.
Now that I think about it, I start to feel like maybe the latter question answers the former...
(Also, though it's been a minute, I'm pretty sure it is possible to implement multi-word commands that don't treat their trailing words as arguments, such that the command might be "seize the horny" instead - I want to say something like 'Seizing is an action applying to nothing. Understand "seize the horny" as seizing. Instead of seizing, [...]' might work, but haven't tried it, so can't make a promise there.)