This may or may not be a bug, as the Tutorial is something of a prequel to the Campaign proper, but I thought I should mention it anyway. Decided to start the Tutorial as something of a break from the Insane maps I've been testing lately. I was a little surprised to see "Achievement Unlocked: For Arcea" show up in the corner when I started the tutorial, as its description states that one gets it for starting the campaign.
I realize that the Tutorial is a prelude to the actual campaign. But in case this is an bug, I'm flagging it for attention. 
UPDATED: Finishing the tutorial will also unlock the "Under Pressure" Steam Achievement which is supposed to be unlocked for winning a game in under 200 turns. While it is technically winning a game, I suspect this isn't what was intended when the achievement was drawn up. 