April 15th, 2008
After installing Aptana Studio, the Eclipse plugin version, it changes the standard Flex CSS editor to it’s own version. This gives you a lot of errors because of the syntax differences. Luckily this can be changed back to normal (Flex) by going to Window > Preferences > General > Editors > File Associations. Here you can change the default editor for the CSS file type from the ‘Aptana CSS Editor’ to the ‘CSS Editor’. Then after restarting Flex Builder everything should work fine again.