I was hoping that non-subscribers would also have access to 15x15's so that everyone could "share the wealth", but oh well.
I just solved the sample 15x15; following are my answers for each row from left to right:
Row 1 > 6 12 4 8 11 1 15 3 13 14 2 9 5 7 10
Row 2 > 14 9 5 15 7 12 6 10 8 2 13 1 11 3 4
Row 3 > 7 3 8 10 5 2 9 4 15 1 12 14 6 13 11
Row 4 > 15 1 11 2 10 3 7 13 5 4 6 12 14 9 8
Row 5 > 1 8 13 6 12 11 3 2 7 10 5 15 4 14 9
Row 6 > 5 13 6 11 2 10 14 15 3 9 7 8 12 4 1
Row 7 > 10 4 2 5 14 8 13 7 9 12 11 3 1 6 15
Row 8 > 9 2 12 4 3 7 10 11 6 15 1 13 8 5 14
Row 9 > 3 15 7 14 8 5 1 9 12 13 4 2 10 11 6
Row 10 > 13 10 15 1 4 14 2 8 11 5 9 6 3 12 7
Row 11 > 4 6 1 13 9 15 5 14 10 8 3 11 7 2 12
Row 12 > 2 7 10 12 1 6 11 5 14 3 15 4 9 8 13
Row 13 > 8 14 9 7 13 4 12 6 2 11 10 5 15 1 3
Row 14 > 12 11 3 9 6 13 8 1 4 7 14 10 2 15 5
Row 15 > 11 5 14 3 15 9 4 12 1 6 8 7 13 10 2
I was originally going to print-screen my solution, but it's not an http file. I print-screened it in Paint, shrunk it down in Word,
and solved it after resending it to Paint.