For anyone, wondering about event 27 being non-repeatable.
It kind of is non-repeatable without cheats.
If you are familiar with MTool, you can open this game with it and look at switches (basically, flags/conditions, which are checked/unchecked and modify some aspects of the game). Example here:
Note: as far as I know, it can show stuff only when you enter save file in target game.
Note 2: before playing with variables, always make a backup of your save file(s) or else something unexpected may break. Some games may have global saves as well but this game does not have such.
Switches 521-529 handle different parts of event 27. They are translated (according to Google Translate) as follows:
521: No27 Accepted
522: No27 Completed
523: No27 Experienced
524: No27 Delete initial message
525: No27 Seeding press
526: No27 Temporary end switch
527: No27 Push up
528: No27 Back
529: No27 2-hole press
521 handles guy with quest existing in downtown.
525, 527-529 - scenes which are required to complete minigame.
524 handles explanation of minigame (if turned off, minigame will be explained again).
522, 526 - flags regarding quest completion (first, 526 is turned on, probably for post-minigame message, then it is turned off and 522 is turned on so quest could be marked as completed on investigation board as soon as it is taken).
523 - says if quest was completed at least once.
When unmodified, after completion, next flags are unchecked: 522, 526 (as expected) and 523. My suspicion is that 524 being not turned off gives black screen.
In my example, I turned on 523 (it will trigger another scene as if you are here not a first time when you enter room).
Room is black.
I turn off 524 - event finally begins.
But If you try to leave it like this, after first scene this event will likely preemptively end.
To fully reset event 27, next things are needed to be done:
Turn off 523 (optional, leaving/turning it on will remove darkness).
Turn off 524.
Turn off 525, 527-529.
On variables tab (another tab of MTool) set 25 and 26 to 0 (variables 25 and 26 after minigame is completed can be seen on second screenshot).
Explanation:
25:Fixnum:No27 Filming - tracks amount of scenes seen and will end event once number 4 is reached. After event completion is number 4.
26:Fixnum:No27 Stamina - tracks amount of lives "spent", but once values is larger than or equal to 5, visual glitches will appear in minigame when variable 25 is not equal 4. After event completion is number 4 or 5, depending if one life got wasted on duplicate scene or not.
If you are softlocked in event 27:
Black screen - turn off switch 524, and event will begin.
Cannot exit after minigame is kind of completed - set variable 25 to 4 and then turn on switch 526.
So... yeah. My recommendation - open game with MTool, load your save and edit variables yourself, as game doesn't do it for you in case of event 27.
Or just don't bother yourself with it.