The anchor tools in PrPro can be awfully confusing. No question.
Add a text box, the anchor is at the upper left corner of the box.
Add a text line, the anchor is at the lower left corner of the text itself.
Add a rectangle, the anchor point is in the center of the box.
And if you have "snap in program monitor" active, hover over the anchor point on-screen and wait for the anchor symbol to appear, you can move the anchor point and see if and when you center it in the box.
Further, while moving the anchor points in either text type, the text moves WHILE you're trying to center the anchor point. Very confusing.