Latest Spine version issue

Hi anybody using Spine in Unity ? Actually I am facing a problem with latest plugin of Spine, When I use the spine and import it in Unity it says "InvalidCastException : Specified cast is not valid. Error reading Skeleton Json file. " so can you give me an idea how to solve it ? As I am having too many files for the spine, I can not export it from older version of Spine. I have to use the newer version of the spine . So please help me with the Binary files and Skeleton json file to use it properly.

Thanks,

Gaurang