If you have ever received this error:

*** ERROR: For anim <fullanimation>, joint with CRC <0x4446e9b8> not found in basepose.

Mostly when you have tried to make a new basepose on a unit or walker or tried to make a new anim set using an existing basepose here is what it most likely is. Units and walkers use the dummyroot (or highest non enveloped null in the tree*) to do the forward and backward movement. If there are no keyframes for these you will get the error.
The solution is select the dummyroot and make a key frame for translation on the first and last frames. You don't have to move it anywhere just key it.
Now export your basepose or animations and the error should go away.



*on models with a GroundDummy and dummyroot as a child key the dummyroot.