1.0 material editor issue

I wanted to try 1.0 and installed it,
But when I opened material editor, it’s like this :

Am I missing something or is this a bug?

update : I activated demo license, now I can see corona materials. others are still black though.

Others? For example what kind of materials?

default ones for example, archmaterials

The material previews probably just haven’t been updated. As soon as you change a value it should rerender the slot.