LAST EDITED ON 06-27-13 AT 01:13 PM (EST)
1. The first deceased, Sheri -- was she actually a contestant who lost somehow, or was it arranged in advance that she would not actually compete for the prize?
I'm pretty certain Sheri was planted designated first victim, breaking the champagne glass was in the script.
2. Are they going to tell us every week who did the best on the quiz and also who that person thought was the killer? That would seem to give it away well before the finale.
I would say that Sasha did best on the quiz week one, the reveal at the dinner table is used to show who does best at the quiz each week. This is in keeping with the format, that "the Killer" is intentionally seeking out the most worthy adversary amongst the players. On the ABC site they do reveal the killer guesses (though it took the monkeys almost a day to get the page right week 1): http://beta.abc.go.com/shows/whodunnit/blogs/killer-guesses/week-one
Adrianna - Dontae
Cris - Adrianna
Dana - Adrianna
Don - Dana
Dontae - Adrianna
Geno - Kam
Kam - Geno
Lindsey - Cris
Melina - Cris
Ronnie - Dontae
Sasha - Adrianna
Ulysses - Dontae
3. Do they plant clues to the actual identity of the killer as opposed to just how the murder was committed? Or is the only clue the other contestants' possible flubs in the investigation?
There are supposedly some clues planted as to the identity of "the Killer" for the observant viewer. I haven't followed that stuff up (check the Twitter material under Social at the website http://beta.abc.go.com/shows/whodunnit/social-scene ) because I thought it too cryptic and deceptive. Rather, follow the action in the episodes, "the Killer" is to some extent also working off a script and will (I assume) become more of a Mole as the show progresses, get more into character.