Background gradient and globe alpha animation

[Pavel-Ilyin]

1. I need to make background of WorldWindow linear vertical gradient. How achieve it?
2. Initially globe's polygons (glboe sphere and country polygons) appears gradually. It's not beautiful. I want to hide globe until all polygons loaded displayed properly an then reveal the globe with alpha aniamtion, but I didn't find any tools for it. Is there way to reveal globe with alpha animation?