Gott Vater, sende deine Geist

In his preluee to the melody of "Gott Vater sende deine Geist" (which is the same melody as "Kommt her zu mir, spricht Gottes Sohn") Tag writes the introductuin on two different staves, suggesting that these should be played on different manuals. The choral melody than enters on the upper one of these two staves. That was quite a resgistration challenge. In the introduction the two manuals should be balanced, yet the chorale melody should be easily discernable. Perhaps a third manual should be used, but Tag gives no indication of this.
In the end, I decided to change the registration when the chorale malody enters and to change it back at the end of the piece.

Score available here: https://partitura.org/index.php/christian-gotthilf-tag-gott-vater-sende-deine-geist