From https://unity3d.com/unity/beta-download I think the problem is because :
Graphics: Texture is now abstract.
The line with new Texture() now does not work because the constructor is now protected
. Here's a list of all errors so far.
Assets/Spine/spine-unity/Editor/SkeletonDataAssetInspector.cs(660,26): error CS1540: Cannot access protected member UnityEngine.Texture.Texture()' via a qualifier of type
UnityEngine.Texture'. The qualifier must be of type `Spine.Unity.Editor.SkeletonDataAssetInspector' or derived from it
Assets/Spine/spine-unity/Editor/SkeletonDataAssetInspector.cs(660,26): error CS0122: `UnityEngine.Texture.Texture()' is inaccessible due to its protection level
Do you have a quick fix that would not cause problem somewhere else? I just replace it with Texture2D m_previewTex = new Texture2D(0, 0, TextureFormat.RGBA32, false);
and cast Texture
to Texture2D
a bit below that line so that it compiles.