Every time i try to use this API, it always comes back with NULL responses when I try to scrape a website. Why does it do that?

The most common error is forgetting to disable the check_plain() checks by specifying FALSE as the last argument of the function call:

IE: before($this, $inthis); <-- Lacks the check_plain disable feature
IE: before($this, $inthis, FALSE); <-- This should ALWAYS spit back something regardless of the text type it was given unless there was a problem finding the $this or $inthis variable.