I recently encountered this problem and ran a test in CS3. The problem seems to be related to the extra spaces around the include statement between the parenthesis and the quotes:
require_once( "../webassist/framework/library.php" );
require_once( "../webassist/framework/framework.php" );
If those extra spaces are removed, my template applies correctly (adjusting both link references), but the Server Behavior window marks the behavior as broken (displaying the !).
Currently the first is adjusted, but the second is missed.