You should be able to change the graphics options in the demo, but they are not saved when you exit (or the audio options). Presumably this is to encourage people to get the full game, rather than play the demo through multiple times, or something.
I don't recall anyone having a problem with not being able to change any graphics options, though.
Damian is the bald guy who looks at the necklace/medallion; I assume it belonged to his executed girlfriend, or was a gift from her. The guy chasing after the dragon was the main character, or one of the other dragon slayers.
I do not know if there are any death knights in D2:ED.
The Divine One was human, the main character in DD (you start off as one of three marked ones, and after the other two prove themselves to dumb to live, you perform a blessing ceremony to become the Divine One).
I did complete BD, on tactical.
Nobody that I know of has started selling D2:ED early in Canada, so it is going to be another week before I can play D2:ED. I installed the demo on a laptop that didn't quite meet the minimum specs, but response was too sluggish for acceptable play, so I just uninstalled it.
The math appendix in the
Beyond Divinity Strategy Guide gives some general suggestions for stat point distribution.
There is a typo in the last formula in the 'other secondary stats' section; in the formula for evasion, the second term should be speed, rather than survival.
You are past this point, but the topic
Killing Fergus contains a bit of discussion on stat distribution, as well.
Unlike in DD where most warriors pretty much ended up averaging 2 strength, 2 agility and 1 constitution per level, there are many more ways to build an effective character in BD. Some people have made high agility warriors, or high strength or balanced, or something else suited to their playstyle.
Your reputation doesn't have a big influence in the game, though a higher reputation will raise merchant prices (unlike in DD where prices would drop). There is no bonus if you get you reputation above any point (maybe bragging rights?).