(Geonodes)Problem with setting position of certain primitives[Solved]

I want to place a filled Quadrilateral curve (basically, equivalent to Plane) in the center of a particular face. Here is how setup looks with the object at the coordinate center:

The cube marks the position I need it at. But then I actually set the position of a plane (Set Position node in Offset mode), it is completely off

The position coordinates itself are correct, since if I use most other primitives (such as cube), they appear where I want them. Only Quadrilateral spline and Grid (with some particular settings) give this error. What is so special about them?

Here is what happens with Grid primitive. 3x3 (or more) grid functions correctly, while 2x2 is off place

With more tests, I understand even less. Tried to delete select faces of a Cube with Separate Geometry, and it seems that the coordinate center of this new mesh recalculates relative to its bounds

Was my error in accessing attributes.