My spine version is 4.0.62
When I drag exported objects to Unity, I find texture have error about alpha.
This is spine exported texture open with Photoshop.
This is spine exported texture show in Unity Inspector.
This is spine animation in Unity.
This is Spine Texture packge Setting.
by the way, I can't active Spine material Straight Alpha Texture field in Unity, because it can't work on Mobile devices.(I only test in Android.)
This is Spine raw project.
SpineProject.rar