Since we moved to FX 8 b115 the launcher generated by the packager is not able to start SceneBuilder.
The root cause could be the RT-34146, investigation is on going.
The stack below is what one get (tried Windows and Linux for now, stack is identical):

 ./SceneBuilder/JavaFX\ Scene\ Builder\ 2.0.exe
Exception in Application start method
Workaround until RT-13281 is implemented: keep toolkit alive
java.lang.reflect.InvocationTargetException
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:483)
        at com.javafx.main.Main.launchApp(Main.java:731)
        at com.javafx.main.Main.main(Main.java:882)
Caused by: java.lang.RuntimeException: Exception in Application start method
        at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:894)
        at com.sun.javafx.application.LauncherImpl.access$000(LauncherImpl.java:56)
        at com.sun.javafx.application.LauncherImpl$1.run(LauncherImpl.java:158)
        at java.lang.Thread.run(Thread.java:744)
Caused by: java.lang.InternalError: CallerSensitive annotation expected at frame 1
        at sun.reflect.Reflection.getCallerClass(Native Method)
        at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2398)
        at com.oracle.javafx.scenebuilder.kit.fxom.FXOMLoader.load(FXOMLoader.java:81)
        at com.oracle.javafx.scenebuilder.kit.fxom.FXOMDocument.<init>(FXOMDocument.java:71)
        at com.oracle.javafx.scenebuilder.kit.editor.EditorController.updateFxomDocument(EditorController.java:1341)
        at com.oracle.javafx.scenebuilder.kit.editor.EditorController.setFxmlTextAndLocation(EditorController.java:440)
        at com.oracle.javafx.scenebuilder.app.DocumentWindowController.loadWithDefaultContent(DocumentWindowController.java:210)
        at com.oracle.javafx.scenebuilder.app.SceneBuilderApp.handleLaunch(SceneBuilderApp.java:221)
        at com.oracle.javafx.scenebuilder.app.AppPlatform.requestStartGeneric(AppPlatform.java:132)
        at com.oracle.javafx.scenebuilder.app.AppPlatform.requestStart(AppPlatform.java:100)
        at com.oracle.javafx.scenebuilder.app.SceneBuilderApp.start(SceneBuilderApp.java:179)
        at com.sun.javafx.application.LauncherImpl$8.run(LauncherImpl.java:837)
        at com.sun.javafx.application.PlatformImpl$7.run(PlatformImpl.java:331)
        at com.sun.javafx.application.PlatformImpl$6$1.run(PlatformImpl.java:297)
        at com.sun.javafx.application.PlatformImpl$6$1.run(PlatformImpl.java:294)
        at java.security.AccessController.doPrivileged(Native Method)
        at com.sun.javafx.application.PlatformImpl$6.run(PlatformImpl.java:294)
        at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
        at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
        at com.sun.glass.ui.win.WinApplication.access$300(WinApplication.java:39)
        at com.sun.glass.ui.win.WinApplication$4$1.run(WinApplication.java:112)
        ... 1 more