So just for posterity, these are the *new* scenes I found:
Beach > Player at glory hole - Mom blowjob scene
Beach > Player at glory hole - Effie blowjob scene (never seen this before, might be old?)
Beach > Random Changing Room > Catch Sister blowing guy w/ "dont tell mom about this" line (never seen this before, might be old?)
Player Bedroom > Sister wakes you up at night to go to Basement; You are naked
---leads to Building box fort with Sister (no sex)
---leads to Upstairs conversation about "last night" (next day)
*NOTE* At this point the objective tracker says "content completed" for Sister's storyline. You can still do the following:
Player Bedroom > Watch Sister's cam-show (on Wednesday afternoon; her Bedroom will be locked)
---Donate amount up to $200 (I picked $200)
---leads to wake up Sister at night (final wedge of timer OR "late" night/no-wedge; either works) to go to Box Fort in Basement (she is naked); She agrees but needs to get dressed / tells you she will meet you there...
---Clicking on her door displays "She is getting dressed / I should go to basement" message.
And this is where I'm stuck, and I *think* a lot of other people are. You leave her room, but nothing triggers by going to the basement. I haven't seen too many people mention the camshow section AFTER the game says content is finished, so I wanted to just clarify that it exists.
Lastly, I started the game by continuing from the "After Home-Run with Mom" checkpoint in the menu system (not by loading a save from a previous version). Maybe that has something to do with it, but this release is SOOOOooooooo buggy / slow (like seriously, a 1-2 second input delay minimum), playing thru from scratch seems like it wouldnt be worth it.