Are the arc adventures (everything not including the intro adventures) meant to be played in any specific order ?

well, there IS a logical order to them, and some of them make more sense when played in a specific order...

in particular, you should try to play #1 first, as it sets the stage for the story arc...

if you can't play them in order, however, just remember that there is a separation of player and character knowledge...the character may have gone on a run and knows who John Q. is, and then meet up with him in an earlier adventure where he is supposedly met for the first time - just play dumb like you don't know who he is...

it's like watching a TV show/series...if you come into the middle of 24, Lost, or similar shows, and then go back and watch the first couple of episodes, well, you already know what is happening, but do you let that spoil your enjoyment?? no, you just shove it to the back of your mind and say "Oh, so THAT'S why they're doing that in episode 12...."

does that help??