尝试添加新模型 ( add objects -> click model -> add instance to world) 时，我收到一个消息框告诉我An unknown error has occured。实体被添加到对象树中（参见屏幕截图），但不会出现在渲染窗口中。
我第一次在这台电脑上使用 Alice。它在不同 PC 上的早期版本的其他计算机上运行良好。我已经在 Alice 论坛上搜索了这个特定问题，但无济于事。Alice 2.3.3 中不会出现该问题。
Alice version: 2.4.1
os.name: Windows XP
os.version: 5.1
os.arch: x86
java.vm.name: Java HotSpot(TM) Client VM
java.vm.version: 20.0-b11
user.dir: C:\Programme\Alice 2.4\Required
Error during simulation.
javax.media.j3d.CapabilityNotSetException: Appearance: no capability to set transparencyAttributes
at javax.media.j3d.Appearance.setTransparencyAttributes(Appearance.java:374)
at edu.cmu.cs.stage3.alice.scenegraph.renderer.java3drenderer.AppearanceProxy.changed(AppearanceProxy.java:122)
at edu.cmu.cs.stage3.alice.scenegraph.renderer.AbstractProxyRenderer.dispatchPropertyChange(AbstractProxyRenderer.java:38)
at edu.cmu.cs.stage3.alice.scenegraph.renderer.AbstractRenderer.changed(AbstractRenderer.java:220)
at edu.cmu.cs.stage3.alice.scenegraph.Element.onPropertyChange(Element.java:155)
at edu.cmu.cs.stage3.alice.scenegraph.Element.onPropertyChange(Element.java:162)
at edu.cmu.cs.stage3.alice.scenegraph.Appearance.setOpacity(Appearance.java:115)
at edu.cmu.cs.stage3.alice.core.Model.propertyChanged(Model.java:201)
at edu.cmu.cs.stage3.alice.core.Element.propertyChanged(Element.java:269)
at edu.cmu.cs.stage3.alice.core.Property.onChanged(Property.java:427)
at edu.cmu.cs.stage3.alice.core.Property.onSet(Property.java:453)
at edu.cmu.cs.stage3.alice.core.Property.set(Property.java:470)
at edu.cmu.cs.stage3.alice.core.Property.setHowMuch(Property.java:476)
at edu.cmu.cs.stage3.alice.core.Property.set(Property.java:492)
at edu.cmu.cs.stage3.alice.core.response.PropertyAnimation$RuntimePropertyAnimation.set(PropertyAnimation.java:90)
at edu.cmu.cs.stage3.alice.core.response.PropertyAnimation$RuntimePropertyAnimation.update(PropertyAnimation.java:135)
at edu.cmu.cs.stage3.alice.core.response.DoTogether$RuntimeDoTogether.update(DoTogether.java:71)
at edu.cmu.cs.stage3.alice.core.response.DoInOrder$RuntimeDoInOrder.childUpdate(DoInOrder.java:58)
at edu.cmu.cs.stage3.alice.core.response.DoInOrder$RuntimeDoInOrder.update(DoInOrder.java:101)
at edu.cmu.cs.stage3.alice.core.response.DoTogether$RuntimeDoTogether.update(DoTogether.java:71)
at edu.cmu.cs.stage3.alice.core.response.DoInOrder$RuntimeDoInOrder.childUpdate(DoInOrder.java:58)
at edu.cmu.cs.stage3.alice.core.response.DoInOrder$RuntimeDoInOrder.update(DoInOrder.java:101)
at edu.cmu.cs.stage3.alice.core.util.OneShot.scheduled(OneShot.java:56)
at edu.cmu.cs.stage3.alice.core.Scheduler.schedule(Scheduler.java:72)
at edu.cmu.cs.stage3.alice.core.Scheduler.run(Scheduler.java:98)
at edu.cmu.cs.stage3.alice.authoringtool.util.DefaultScheduler.simulateOnce(DefaultScheduler.java:117)
at edu.cmu.cs.stage3.alice.authoringtool.util.DefaultScheduler.run(DefaultScheduler.java:78)
at edu.cmu.cs.stage3.scheduler.AbstractScheduler.run(AbstractScheduler.java:45)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:641)
at java.awt.EventQueue.access$000(EventQueue.java:84)
at java.awt.EventQueue$1.run(EventQueue.java:602)
at java.awt.EventQueue$1.run(EventQueue.java:600)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:611)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
