If you experienced difficulties with the Java-based structure editor, please read below.
SciFinder now also provides a non-java structure editor. You may select your prefered editor on the interface easily.
CAS provided a solution to Java 7 Update 51 problems.
For trouble shooting, please check your Java version on this site http://javatester.org/version.html and check this page from CalTech for some validated configuration.
If you have the latest version of Java, you may try to open the Java Control Panel then click on the Security tab to click the Edit Site list. And add https://scifinder.cas.org to the list.
If nothing above works, you can download the Structure Editor from SciFinder on this page as an alternative.
Please contact me if you have additional questions.