why no textures after package, destructible mesh?

somehow after package to windows all my destructible meshes with texture are checkerd after package? anybody knows whats going wrong. First time i experience this. And it only happends with textures i made myself, like photos >material. Textures of UE4 packages are allright!
It only appears with destructible meshes, all the others go well.
I use 3.13 at the moment,

hope somebody can help me out, tried allready so many things!

i made a little youtube to show whats happening. Eversince i use 3.13 i have this problem, or is that a coincidence?

I have the same issue in 4.15. Everything looks fine in the editor, but when running a packaged build none of my destructible meshes has materials applied.

Are your materials displayed in the file structure of the compiled application ?

And you could test the same material on a static mesh and see if it only happens to one of them.