So a mate of mine and I started the Portal 2 co-op mode last night after picking it up cheap in the sales but I'm not 100% sure if we've started in the right place/order!?!? 
From memory we went through the "calibration" tests fine and ended up in a room (I think its called the "hub") with a normal exit door around a corner to the left but also a small room suspended over to the right with two big red buttons in it that you had to portal over to.
Instead of going through the regular exit that you walk to, we went over to the 2 big red buttons and stood on them and it transported us to another room with two buttons, an arrow right and an arrow left - we clicked the arrow left and went through a door and started the game - the problem is I dont know what we have missed/bypassed by doing this rather than going through the usual door!?!?!
I must admit, the puzzles we have started on seem to be quite tricky for the beginning levels (if thats what it is!)
Can anyone tell me if we are doing things in the right order???
Thanks......

From memory we went through the "calibration" tests fine and ended up in a room (I think its called the "hub") with a normal exit door around a corner to the left but also a small room suspended over to the right with two big red buttons in it that you had to portal over to.
Instead of going through the regular exit that you walk to, we went over to the 2 big red buttons and stood on them and it transported us to another room with two buttons, an arrow right and an arrow left - we clicked the arrow left and went through a door and started the game - the problem is I dont know what we have missed/bypassed by doing this rather than going through the usual door!?!?!

I must admit, the puzzles we have started on seem to be quite tricky for the beginning levels (if thats what it is!)
Can anyone tell me if we are doing things in the right order???
Thanks......