After finding have large the game is, with only still 1 character made by 2D Spites Animations,
I have been testing for long how to use the Spine 2D skeleton animations directly in UFE

Without a few posts on this 2D issue I can reference to.

So,Spine-Unity runtime allows me to create a SkeletonMecanim Controller,
I can make a GameObject with Skeleton Mecanim and the Hit Boxes Script added
but when coming to the Hit Box Editor,
Character Preview: Spine Mecanim GameObject + Animation Clip from the Controller, just don't work:
When Preview is On, I can only get a freeze image

Even if I create a Hit Box on it, fitting into the Character file,
it still only result in a freeze image in game play.

Despite I am really new to programming things, UFE seems to be the only easiest way which may turn my idea into an actual working game.
Really wish can get some help in this Spine->UFE issue, when this is generally one of the most popular software for skeletal 2D animations.

Besides, I have got the UFE2 Source.
May changing the coding in Animation and Preview Controls of the Hit Box Editor or something make it easier to work between Spine and UFE? I don't know...
(I will gladly pay for it if someone can help me in this part of coding...)