[LayaAirIDE 2.0]使用LayaAirUnityPlugin_beta插件的时候在Unity预览报错

laya.d3.js:25772 Uncaught TypeError: Cannot read property 'transform' of undefined
    at SkinnedMeshRenderer._computeSubSkinnedData (laya.d3.js:25772)
    at SkinnedMeshRenderer._computeSkinnedData (laya.d3.js:25754)
    at SkinnedMeshRenderer._renderUpdate (laya.d3.js:25851)
    at RenderElement._render (laya.d3.js:14094)
    at RenderQueue._render (laya.d3.js:24125)
    at Scene3D._renderScene (laya.d3.js:25463)
    at Camera.render (laya.d3.js:13925)
    at Scene3D.renderSubmit (laya.d3.js:25632)
    at Context.submitElement (laya.core.js:9421)
    at Context.flush (laya.core.js:9427)