In fact, it's running pretty well.
But I still got the bug with invisible background + sprites.
2-Ah friend of mine was trying to play my game. Several friends got it working, but this one got a bug. There is one layer, where the tiled background + some sprites dissapears. But other sprites on the same layer still there.
More people who tried to play it, reported me that.
I Don't think their browser is not updated. One of them was using Firefox 8. Don't think its graphic cards issue either.
This is the game: