I've installed the Roboto typeface on my system but it turns out that the default, regular face is rendered as black, even though in the thumbnail it appears to be lighter. This happens on all applications, on Linux and Windows too. Here's an example:
This is how the thumbnails look on any file manager on Linux, the fonts seem fine (Windows doesn't even list the . Windows only lists the regular face on the collection)normal face if I remove the black face:

And this is how it looks once it's rendered, no matter on what application:

Any application that asks for the Roboto font, renders its black face instead. Google Chrome on Windows and Linux, side by side, for example:

I've tried removing the black face and symlinking to the and it works (Windows and Linux result, side by side):regular one with the black's filename,

But I lose my black face and the italics are still rendered with the black face, so I'd have to remove the face along with its variants. What can I do? Is symlinking removing my fonts the only solution?
Update:
The problem is that both variants of the font (regular and black) interfere with each other, and I can only have one of the two installed at a time. Is there some sort of font metadata that I could change to fix this?