Why landscape material doesn't work on mac?

Hello guys! Here’s my question: Do you ever developed something on MAC? If yes, why my landscape material doesn’t look correctly only on MAC? (for example on Windows and Linux it is ok). Seems like it can’t afford to have more than one layer in the landscape material cause if I click “Fill layer” with one of it, it works. I’ve searched on the web but there are very few informations about MAC development in UE4. Thank you very much!