Thanks for the help! That helped.
I found another error. When imported Spine-unity runtime into a new project without 2DToolkit these errors.
Assets/spine-unity/Asset Types/SkeletonDataAsset.cs(41,24): error CS0246: The type or namespace name `tk2dSpriteCollectionData' could not be found. Are you missing a using directive or an assembly reference?
Assets/spine-unity/Modules/TK2D/SpriteCollectionAttachmentLoader.cs(39,25): error CS0246: The type or namespace name `tk2dSpriteCollectionData' could not be found. Are you missing a using directive or an assembly reference?
Assets/spine-unity/Modules/TK2D/SpriteCollectionAttachmentLoader.cs(47,58): error CS0246: The type or namespace name `tk2dSpriteCollectionData' could not be found. Are you missing a using directive or an assembly reference?
I hope it somehow help you.