I bought DAO early (2009) and started with a Dalish Rogue. Naturally I went to Brecilian Forest first after Ostagar, and I soon realized that I neglected his trap disabling skills (remember that heavily trapped room in BF Elven Temple?). So I restarted the game with a new Dalish Rogue, find out by sheer chance that trick with the traps at Lothering, gained a few levels with it and the necessary disarming/unlock skills. Everything went quite decently from that point. Finished the game on normal with a few reloads, then finished even easier on Nightmare. My guess is DAO innitially had some difficulty setting problems at boss fights on normal.
But I was lucky being experienced with Bioware RPG`s. Played BG1&2, NWN. My first attempt with a RPG was with Icewind Dale. It was a birthday gift from a friend (a huge RPG fan). And I knew absolutely nothing about RPG games and D&D rules. I started badly (no multi-class characters, no retry of stats, not even rearranging of them). I got it wrong with THACO and Armor Class (it seemed logical: the higher the better). Somehow, by sheer determination I finished that first play after hundreds of reloads and boss battles 1-2 hours long at least (even the small boss ones). My friend howled with laughter when I told him, and gave me a D&D rule book.
Back to DAO:
One of the most embarrassing moments when playing DAO was when I finally discovered the camp option. It seemed a bit crazy that DAO has no option for resting, but I figured out that since mages needed no spell memorizing (unlike BG & NWN) rest would not be necessary. Then I hit the camp option by accident when using the map for traveling...
I also have to mention a very strange scene with the forest fog in Brecilian Forest second area. I tried so many times to pass the fog in different ways that some Elven spirits appeared and talked to me about the fog and how to get past it. A year later I tried several times to get that scene with the Elven Elder Spirits again, with another Dalish. I never got it again. Maybe it was changed by subsequent patches. Does anyone witnessed that scene with the Elven Spirits when trying to pass the fog?