It is designed to have to roll forward a few rotations of the wheels before it goes into 4x4 lock. Just like a 4x4 truck. That is perfectly normal. And the shifter is stiff on all of them at first. Again, normal.
Just got mine yesterday. It too is shifting a little stiff. I think it's just a break in issue since everything in the linkage seems properly aligned after I looked it over. Time will tell but I think it's just a "new rig" issue. I will let you know if/when mine smooths out.