July 24, 2025 2:08 AM (GMT+2) It seems like it could be opened somehow. Certainly related with Patent for high pressure condenser. Perhaps I need to draft Boiler Room and then I’ll be able to activate the mechanism?

August 16, 2025 11:51 PM (GMT+2) Just drafting the Boiler Room is not enough to do anything. I’ll have to obsess a bit harder over this the next time I get the chance.

August 19, 2025 7:40 PM (GMT+2) The solution was to connect the steam power to the apparatus shown on the left in the Patent for high pressure condenser (I was a bit blind the previous time). Then the apparatus on the right, located besides the Suspicious red door at the underpass, gets powered and you can press it to open the door. This reveals a path to something amazing (see Underground castle ruins). Mystery solved!