Have a new .375 in hand. As I recall, one thing to do is butter up the bolt with Flitz and work it a couple of hundred times to take some of the hitch out of the action. Any other suggestions for simple tunes on a new CZ Safari? I'm thinking crossbolts are not needed in .375.

The recoil lug rests against a rubber pad (at least the 2 I've had did), I'd suggest bedding the receiver from the front of the mag well to 1" forward of the front receiver ring.
Bedding the "F" block would be the next thing to consider doing.
Watch for a "lip" or step at the back of the receiver/mag box, it can hang up feeding IF it's there (simply removing the sharp corner will cure it).

Thanks Tailgunner. I'll open her up and take a look for that lip.