Hmmm....
What are the colors you used?
Try the grey color that is used at most standard noseart as background color if possible.
Did you look at both sides of the nose?
The upper and lower half are each for one side, and since a lot of noseart is singlesided...
It sometimes takes a while to cache the file. I had the same problem a while back , then after trying things for about half an hour, most of them came through.