Can't speak for most files I can't open, but the 4 vids should be:

movies/codex/max1
movies/contact_continental1
movies/codex/continental1
movies/codex/chico1

Yeah, they're "pick one of 3, but 1 can do nothing"... instead of just using "66% chance to execute 1 of these 2"... though sometimes I do wonder if they are intended blank or just empty cause of error, since the non-raw sometimes also omits intended stuff that's just never called upon (the cokedealers of Green Bridge for example).

You don't... they shipped these with the game by accident last beta (along with a bunch of other wip projects and dlc-prefabs), they're not supposed to be in the gamefiles (rather being handled serverside by Steam).

They rather have reports per topic per heist though, makes it easier for them to just reference topics to bugs, and close them on an individual basis, which a large collection wont allow.

If you don't want to report them, mind if I do?

Again, post in Bug Reporting, nothing much we can do about that here, none of us are affiliated with Overkill.

You were pretty much spot on though, hence asking to post it in BR.

Biker is Born (day 1) and Chew (day 2). Prison Nightmare is Help.

We don't know, why don't you post in Bug Reporting to the people who could answer that?

20 is about the avarage amount of gage packages. A few maps have less, and some have more (a lot more for Birth of Sky IIRC).

The locations also shift with patches, or get outright deleted (Four Stores, probably the one inside the wall I reported), or added (Lab Rats IIRC).
... and still they haven't done anything about that Hoxton Breakout day 1 one :/

They tried to fix it, and failed.
Tying up or killing the welder will prevent FPS from dropping.