Stepchart creation failed!

invalid SM file: measure with a strange number of notes (15 notes at line 54), notes are: array(15) { [0]=> string(4) "0000" [1]=> string(4) "0000" [2]=> string(4) "0000" [3]=> string(4) "0010" [4]=> string(4) "0000" [5]=> string(4) "1000" [6]=> string(4) "0100" [7]=> string(4) "0000" [8]=> string(4) "0010" [9]=> string(4) "0000" [10]=> string(4) "0010" [11]=> string(4) "0011" [12]=> string(4) "0110" [13]=> string(4) "1100" [14]=> string(4) "1001" }