I had a quite pleasant time reading this one! The mix of mechanical disaster and alien body horror stuff is very potent and well balanced. I like the creature, I think the level of detail on the tower's construction/features/what can be salvaged from where is really crunchy and useful for directing players' decisions. I also really enjoy how high everyone's stress skyrockets at the front of the session - I'd say throwing on an immediate panic check would be a cheeky bit of fun too.
Visually, I feel things are solid if a bit all over the place. Some of the content on the outside panels could probably be moved inside, and I think a small bit of direction on how to pace the siren's attacks over time would be good. I noticed a handful of grammatical quibbles too but those can definitely be ironed out post-jam, and the intent is always clear.
Really fun module all around! Great work!