it's interesting because I have MATE installed in several distros. some draw icons properly, some don't. the two I know work are Ubuntu 12.04 and SalixOS.(slackware) however I have MATE installed on top of Bodhi 2.0 which is suppose to be based on Ubuntu 12.04 and it doesn't work. neither does antiX, crunchbang, semplice which are all debian based. strange.