Your program, as presented, will not work.   Suppose that File::Find::find created a list something like:

/home/transiency/dir*one
/home/transiency/dir*one/file*one
/home/transiency/dir*one/file*two

After you rename '/home/transiency/dir*one' to '/home/transiency/dirone' then your program will not be able to find and rename '/home/transiency/dir*one/file*one' and '/home/transiency/dir*one/file*two' because '/home/transiency/dir*one' does not exist anymore.   You need something like:

#!/usr/bin/perl
use warnings;
use strict;

use File::Find;

our $VERSION = '0.1.3';

### NAME NORMALIZER ###

my $DIR = shift @ARGV;

opendir TOCLEAN, $DIR or die "$DIR: $!";

my @dirs = map "$DIR/$_", grep -d "$DIR/$_" && !/\A\.\.?\z/, readdir T
+OCLEAN;

finddepth sub {
    ( my $new = $_ ) =~ tr!a-zA-Z0-9.~-!_!c;
    return if $new eq $_;
    rename $_, $new or warn "Cannot rename '$_' to '$new' $!";
    }, @dirs;
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