ObCanonical-JAPH-version:

$_="+2\"0->6+w-43-28-Q-20-5+K+g+1+f-1/-13-8+7+L-13-48-13+12-1-A-1-43";
s/[">\/A-wild;]/ord$&/eg;while( /[-+]\d+/g ){  @a or @a=($&) and next;
unshift @a, map {($_+$&)/2 => ($_-$&)/2} pop @a; } print map chr,  @a;
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Create your own messages:

my @a = map ord, split //, "<your message here>";
my @b;
while(@a){
        $#a or unshift @b, @a and last;
        my $c = shift @a; # ($_+$&)/2;
        my $d = shift @a; # ($_-$&)/2;
        unshift @b, $c - $d; # $&
        push @a, $c + $d; # $_
}
unshift @b, undef;
$_ = join "+",@b;
s/\+-/-/g;
s/[3-9][0-9]/($&>=32&&$&!=43&&$&!=45&&$&<48||$&>=58?chr $&:$&)/eg;
s/1[0-2][0-9]/($&<127?chr $&:$&)/eg;
print "$_\n";
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