White Landscape after normal loading screen

[Gimlis_Goldfisch]

I just installed Tekkit Lite for Mac and tried to create a world. Everything was normal, just the whole landscape was white, except the Minimap and the health bars. When I opened my inventory, the screen behind was as normally darker and i could see the blocks. I also changed my texture pack a few times. Who knows what is wrong? Plz help me

(Sry for my bad english i'm german)

Gimlis_Goldfisch