According to the Release Notes of Java 7 Update 45, the applet could fail to load by throwing a NullPointerException, if caching is disabled.
The SignLive! CC cloud suite applets use two Manifest attributes (Permissions and Caller-Allowable-Codebase), which enforce, that Jar caching must be enabled in the Java Control Panel. Otherwise the applet will fail loading.
If a JAR file is using pack compression with manifest entries Permissions and Caller-Allowable-Codebase while deployment caching is disabled, then:Source Java 7 Update 45 Release Notes.
The Caller-Allowable-Codebase attribute will cause the applet to fail to load by throwing a java.lang.NullPointerException.