I can only answer one question off the top of my head.

Code:
; $chr(36) == $
; $chr(37) == %
; $chr(123) == {             
if (($chr(36) isin $2-) || ($chr(37) isin $2-) || ($chr(123) isin $2-)) { return }



If you like http://www.asciitable.com/index/asciifull.gif or you can find the $chr() for them on your own

Code:
//var %x 127 | while (%x) {  echo -ag %x - $chr(%x) | dec %x }