try running this:

while ((my $counter=0) <100){print $counter++};

$counter is always 0, the syntax of the while is wrong

try declaring $counter before the while, or use

for (my $counter=0;$counter<100;$counter++)

and ditch the $counter+=1.

Its keeling over in createNP by the way. I found that out by putting in "print "foo\n";" in various places until it didn't get printed. Simple but effective!