The EGG file you are loading has not been set up properly to be loaded as an Actor. Generally this will depend on how you exported the EGG file. If the gorilla does not need to animate, you can simply use loader.loadModel instead of creating an Actor. If the gorilla has bones inside and needs to animate, then you need to export it differently. Specifically you need to export it in a way that adds the “Dart” flag in the EGG file.
This thread may be of use:
[url]Problem with animation using actors, help plz]