Without seeing the Photoshop Document with the imported smart object layer structure we have no idea of the document structure, It looks like the smart object has a white background and the document it is imported into has add a gradient to the white background. Easy to do by selecting the white background then adding a empty layer that you fill the selection with a gradient that goes gray to white. Or use the inverted selection to mask off the white background and reveal a gradient layer below. Ther are alyway more the one way to do things in Phoroshop. Blending the layer in mutiply could also blend in the gradient
HI!, thanks for your answer. The background layer was not important ... I had created and then imported the object, but the error was the same.
Anyway I solved ... I removed the photoshop preferences from the library / preferences folder, recreating them. Now the program works properly!