[luis.hijarrubia]

Note: the issue is only with empty untitled.mxs scene, if you open an existing scene, the project folder is used correctly.
Materials web browser seems to be not importing materials. It's a configuration issue, if you have marked use project folder seems to be using the path below anyway, and if that path is empty or slashes or some folder that do not exists it fails importing. Please uncheck the save files on my project folder option and select an existing folder. This should make it work. And we will fix this from instalation on next patch.