Made the secret passage from floor 1 to floor 2 more obvious and fixed the issues with the stairs as mentioned by the latest commenter. Hope this helps!

Edited based on a critique from one of the players and completed the appearance of the build a bit more. A bush wasn't usable at first but I've fixed it since.

Redid the second and fourth floors and added security to the third floor, as requested by a recent player. Also added a secret passageway linking the first and second floors.

Added some secret passageways and eased up on the difficulty.

Did some major toning down on security, made the passageways in floor 2 bigger, added some computers on floor 3, changed the pickup items on floor 3--overall just some major changes to the level.