Eliot Feld's Ballet Tech presents KIDS DANCE, an ensemble of 40 dancers, ages 9 to 14, in a program of works by Eliot Feld, including the premiere of KYDZNY, set to music by the Raya Brass Band (who will also appear live on opening night).   Also on the program is the merry hoe-down "Apple Pie," music by Bela Fleck & Joe McCracken; and the ingenious "A Stair Dance," music by Steve Reich.