According to the iClone manual, it should be possible to use IK with non-human characters using Bone Edit Mode in the Edit Motion Layer panel and enabling the IK Constrain option. However, the following steps will demonstrate that IK currently seems to be broken for non-human characters:

- From the Content Manager, load Actor -> Avatar -> Non-Human -> Horse (for example)
- Go to Modify -> Attribute and turn spring effects off (to ensure that spring effects are not causing the issue)
- Go to Modify -> Animation -> Edit Motion Layer and enable 'Bone Edit Mode' and 'IK Constrain'
- Ctrl-click a bone to set the base of the IK chain, then click another bone to set the end of the chain
- Press 'w' to enable the Move widget and try to move the end of the chain

Eventually the IK chain will start to glitch (i.e., the lead bone will suddenly refuse to move, or it'll start jumping all over the place). I seem to having this issue with all non-human & prop IK chains.