I found 2 Problems/Bugs on cmsms:
1. if you ( unintentional ) leave opened html tags ( like in my case an opened comment tag - I manipulate the css file in Golive and copy it back to the form, here I created the problem) than it is not more possible to change the css again because the html tags will be interpreted - a good solution could be, convert html specialchars by php or a parser that filter the out of the css text
2. because I crashed the css style ( see above ) I want to delete it and save it again without the html tags, I get the message "file is in use by another page" or somthing, THATs right, but if I delete not by clicking the trash symbol of the style, but instead select the box and click on delete button, the css file will be deleted without this page-check!
Sorry, if my english is trashy, only my school english (german).
Hope I could help (and you understand nevertheless

best regards
Jens