Blue smoke makes me think of an injector issue (Which is a known issue on both 1.3 and 1.7 Cdti's unfortunately

). That really s**ks because the 1.3 is a nice little engine anyway...
Problem is that injector failures may occur at whatever mileage, have seen 1.3's not having the issue before 40.000 miles and some having them with less than 10k... Mine has around 20k miles and still nothing wrong.
Anyway if your car's still under warranty I'd suggest letting VX have a look at this.