Creature & Animal
From external 3D tools to iClone:

Required version: 3DXchaneg4 PRO and above
You are suggested to export non-human characters in FBX format, and then convert them to non-human character via 3DXchange. The character can then be animated with the iClone IK/FK key editing tools.

From iClone to external 3D tools:

Required version: 3DXchaneg5 Pipeline and above
You are suggested to export the non-human characters with animation in FBX format. You may choose a creature or animal from the iClone Content Manager or directly download it from Marketplace into 3DXchange.

Below are some examples on how to import, and export, human character between iClone and other tools.

3ds Max & iClone

You may import and export non-human type creatures between iClone and 3ds Max via FBX. The embedded animations inside a character can also be brought in for further motion IK/FK refinement. For 3ds Max, you may also use the iClone plug-in to convert. Please login to read the white paper on this subject in the developer center.
3ds Max Content to iClone - Whitepaper

Maya & iClone

You may import and export any non-human type creatures between iClone and Maya via FBX. They too can keep their embedded animations for further motion IK/FK refinement after conversion.
Maya Creature to iClone - Tutorial