Gaël Liardon is a French composer who writes music in a mostly Baroque idiom. This choral prelude is based on the model of "Herr Christ, der ein'ge Gottes Sohn", BWV601.
Applying the models of the Orgelbüchlein to other choral melodies, is, I think, exactly what Bach intended with his collection.
See "http://imslp.org/wiki/Category:Liardon,_Gaël" for more of Liardon's work