JGecek लिखाAs for overriding Texture Compression, I would assume it's all correct because I don't know what that is or how to tweak it , lol.
The override settings for other platforms are the tabs next to the "Default" tab, you can enable overrides for Desktop, iOS and Android there.
Regarding the Advanced section, you could disable mipmap generation, as these can create artifacts.
If this still is not the cause, could you please send us the problematic assets (the three exported files) as a zip package to contact@esotericsoftware.com or attach them to a forum posting here. Then we can have a look at it.
