Alright, finally after dicking around in CAD's script I found out how (i used to know but i forgot)
If it's arms, they cannot be perfectly straight, they have to be bent out of position, so I usually set up my origins with them.
1. Then, create an IKHISolver from the start bone to the endbone. Rename this to whatever, I don't care.
2. Then, create a dummy (helpers>dummy). move it to about where that bone is. Create an orientation constraint the end bone to the dummy.
3. Create what you want to use as your "controller" ie: splines like in CAD's tutorial, or a dummy (however, I have had problems using those as controllers in the past.)
4. Link the dummy and the ik constraint to the controller
5. ???
6 Profit!
You can use this for basically anything, however, i STRONGLY recommend using biped systems for skeletal bodies (people, aliens, such) because they can plant their position and rotation (ik is completely locked, and FK is un-locked) for bones. (if you create a running animation for halo, they dont have to run in place, i'm not sure why peoiple think this)
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