--IT TURNED OUT 2B A MOD. WELL PLAYED MODDERS. :)
Latest version of the steam game. I'm sure that this works with other versions too.
Tested this out in multiple chapters and also after activating the 3 subtowers at the start of Ch 17-01 and after activating the main tower.
There's nothing.
IMO this will probably be a new content (though i'll still waste my time to search the trigger).
Ещё видео!