The devil is in the detail and your snapshots helped. The code in the first post needs some attention as it has the extra slashes in it and also the regex.
The code in the first posts works if you dump it in to a text file and then import that text to your Custom Tag editer, by way of the "Import New Tags" button at the bottom. The newly imported tags will be prefixed with "new", so as to not be confused with your current tags.
The additional backslashes ( \\\\ ) in the OP's code, are intentional. They escape the following backslash.
You can read more on that at
http://php.net/manual/en/regexp.reference.escape.phpI'm happy to hear that you finally got it all worked out
cheers!
