Probably the nicest way to get newlines and indentation in snippets is to create the snippet in a new window, and copy and paste it into the snippets box.
However, if you want to enter a linebreak or tab character directly into the snippet window, hold down option while you hit the return or tab key.
The “if” snippet is probably a PHP snippet. Currently the only way to modify that is to override the PHP.sugar according to these instructions:
http://wiki.macrabbit.com/index/Override_default_sugars/
For step #4 instead of changing the Languages.xml file, you will want to modify this file:
PHP.sugar/TextActions/Snippets.xml
The relevant snippets are inside the <text> elements. Here’s some documentation for the XML and snippet syntax if you are confused by the file layout:
http://wiki.macrabbit.com/index/Snippets/
http://wiki.macrabbit.com/index/SnippetSyntax/
