Center Text on Single Page

Or you can set FrameAbove for tag Title, and use an empty named frame from a Reference Page that is just under half a column high.

FM has no mechanism for vertically centering text within a standard text frame. However, it can do it within a table cell. SO, you could possibly use a single cell table with the row-height explicitly set to your text frame height. Don't forget to set the Space Below in the anchoring paragraph to the same negative value as the Space Above for the table, so that the table can reside on the first page over top of the anchoring paragraph (i.e. no gap at the top of the text frame).