Lesson number 1:
If the pattern calls for sport weight yarn in cotton, don't only get the correct weight yarn but fiber as well. I bought sport weight to make a beautiful Robyn Chachula cardigan but purchased superwash wool, well the pattern called for cotton. The wool stretched out so bad it was a total loss. Cotton and wool are two different species. My gauge was correct, I had all my ends weaved in and blocked it. Ugh what a mess, I can't even unravel it because of the motifs connected as you go.
Learned: from now on pay attention to the fiber as well as yarn weight, the designer picked it for a reason.