Cannot erase from WD TV Live Hub - MAC

I just bought the WD TV Live Hub and i’m already annoyed!

I seem not to be able to erase from it! and i don’t know what i’m doing wrong. This is what i get:

Also, if i want to ‘open’ the subfolder “The Walking Dead” for instance, this is what i get:

I hope somebody can help me with this, thanks.

Gotta wait for a moderator to approve the pics.