refinements to preset_node_array.pd abstraction

pd/doc/5.reference/preset_node_array.pd

-#N canvas 125 105 456 572 10;
+#N canvas 290 90 456 572 10;
 #X obj -30 451 until;
 #X obj -30 473 list append;
 #X obj -30 495 list split 1;