According to the skill sheets "Did not inflate both cuffs properly" is a critical fail. This could fall under that? I read that line as meaning you didn't fill them with the proper amount of air though I suppose it could also mean you did it in the incorrect order. The combitubes I have seen are numbered though I thought....
Inflating the larger cuff causes the tube to move around till it's seated properly. If you inflate the small cuff first, and the tube is through the vocal cords, it can cause some serious damage as the tube moves around when you inflate the large balloon.
Critical fail or not, it's not ok to inflate the small cuff first.