Alternatively you could try drawingRoutine: 0 (Soldier) by using the leg frames for the body instead of the torso frames.
This approach has its own challenges as the right south west facing arm needs to be shaved a bit to hide it behind the body.
The reason is that now that the legs instead of the torso are being used for the body the south west arm is rendering in front of the body frame instead of behind it.
Syncing the motion of the torso with the walking arm frames was a little tricky but I think all of them are aligned in the example unit sheet I attached to this post.
Additionally three extra walking frames were needed so the end of the walking loop may need a slight touching up.
As far as I can tell, this does function.
The drawing routine I meant was drawingRoutine: 1
The advantage of drawingRoutine: 0 (Soldier) is access to the flying frames use by X-Com's power suit unit sheet.
If you do not plan on using those frames then as Dioxine said drawingRoutine: 1 (Floater) is most likely much easier to work with.