It's still buggy today, but at least I got a better feel for it. The cut-scene selector, as Joph said, is optional. Still lots of these errors:
I also had issues with it not finding my DA:O (and DA:A) characters. However, I read online that the only thing importing a character does is select your looks, race, gender, and origin. I think it also imports a couple other things (see below)
All the other choices need to be manually changed. Which sorta sucks. I know for a fact I didn't fail to recruit Leliana or let Dog die, for example. Having to manually select a couple dozen items is annoying.
It does import your achievements from the prior games, but I don't think they have any effect. It also tells you how much DLC you own... which is weird. Thanks for letting me know I only have 43% of the DLC for DA2, I guess? I can easily see it become a one-stop shop, saying "Oh, you don't own Item Pack 3, buy it now!"
When the video/cut-scene part isn't crashing any more, I'd like to see if I can go to the Tapestry first, select everything I want, and then have Varric narrate the entire thing. That would be pretty neat.
Oh, and one thing this is great for is to remind you of choices you didn't know you had before. For example, I only played the Dwarf Noble origin to get the achievement, and never realized some of the choices that came from it later. I also need to check up on certain things, like why if the Warden kills the Archdemon, Alistair and Anora cannot be wed in the ending. I could have sworn I had a Hardened Alistair marry Anora and I had an old god baby with Morrigan while giving the final blow to the Archdemon myself... maybe I had Loghain do it?