After that tutorial you will have your 3D animation converted into sprites. That open ALOT of possibilities.
Note: I already tested it, it work. But I never tested it with GE yet.
First get your bone animation a full 3D character.
Then you need to download a free application FragMotion. I think it still free, but you get a bugging once in a while telling you to buy it. But you can keep using it. I have the full version, so I am not sure anymore.
Look at what format you can import. Look at the link.
http://www.fragmosoft.com/
1. In your 3D modeler application export.
2. Export.
3. In FM, import.
4. menu, tool, sprite
Start angle is the rotation of the character around the global y-axis where the first sprite image will be generated.
Spin angle is the amount that the character will be rotated around the y-axis. The increment is equal to the sweep angle divided by the number of rotations.
Width and height represent the 2-D width and height of the resulting image when the camera is looking down the -z-axis at the character in its initial pose.
When the sprite is created an xml file is generated that contains information which can be parsed by a user defined application.
Attachments can be created on the skeleton to save important 2-D positions within the exported images. Attached characters will also appear in the sprite images.
When Uniform Sizing is checked all images in a grid or a strip will have the size of the largest image.
When capturing sprite images from a model using vertex animation it is recommended that Frames be set to match the NumFrames value in the selected animation. This will prevent any interpolation errors.
Show us some results.