updated to css-js-booster 0.2.1, have 2 links to non-existent css in my html:
<link rel="stylesheet" media="screen" href="http://blog.futtta.be/wp-content/plugins/css-js-booster/../../../../../../3f540bbd99f8ebecb73880a685db76ae_plain.css" /><!-- Booster had a problems finding /var/www/blog.futtta.be/wp-content/plugins/css-js-booster/../../../../../../3f540bbd99f8ebecb73880a685db76ae_plain.css -->
link rel="stylesheet" media="all" href="http://blog.futtta.be/wp-content/plugins/css-js-booster/../../../../../../cd545966a09cb9df4446610a68c9e1ed_plain.css" /><!-- Booster had a problems finding /var/www/blog.futtta.be/wp-content/plugins/css-js-booster/../../../../../../cd545966a09cb9df4446610a68c9e1ed_plain.css -->
this was not the case with 0.2.0 as far as i know.