Following this solution to create dynamic css instead of inline css from sorich87 I get an error when requesting the dynamically generated stylesheet. Css is in there but also the default wp error page and a 404 header returned.

Solution I used:
https://wordpress.stackexchange.com/a/1454

My stylesheet url with 404 error:
http://tegelzetbedrijf.net/wp-content/plugins/wp-google-fonts/googlefonts.css?build=20120126

Any suggestions are highly appreciated!
Thanks
Quokka