my $dash = '-';
my ( $prefix, $suffix, @range, );
my $format = "%s%d%s%d";
my $args = [$prefix, $range[0], $dash, $range[1],];
$prefix = "stuff";
$range[0] = 2;
$range[1] = 10;
my $new_name = sprintf ("$format", @$args);
print "NEWNAME -> $new_name\n";
[download]

Should print: NEWNAME -> stuff2-10 But I keep getting: NEWNAME -> 0-0

The problem here is that you are initializing @args with a list containing the values of $prefix, $range[0], $dash, $range[1] before the values are set. In other words, you are assigning a list containing [undef, 0, '-', 0] to $format. If you move the @args assignment below the assignments for $prefix and $range[0..1] you should get the results you were expecting.

HTH,
Josh