No, I never tighten the hopper screw and treat all my grinders with kid gloves.
The Compak K10 has a narrower and deeper neck than the Mazzers. On one hand, the Compak's narrow/deep neck increases the depth of the bean column, so even 1-1/2 shots worth of coffee eliminates popcorning. On the other hand, it means the hopper has a narrower base fitting into the neck, which I believe leads to the hoppers cracking more frequently. For what it's worth, both the standard and mini hopper on mine cracked, but neither to the point that it separated (yet).