I don't get why there is a black line through the moon when you can see I blended it in the tile, and there isn't a black line through the bottom right coren4r where I blended in the pink there???

Actually BluJeann, I think the problem you might be having is that you're changing the border pixels to make your blends. What you should be doing is leaving the border on a separate layer, untouched. Then on a layer below you should draw your tiles and blend that to the untouched layer. When you submit your tiles they are cropped at the 128x128 square and don't include the borders that you are given. That's why the tile has edges on the quilt but not in the checkin tile.

Did that make sense? It's kinda hard to explain.

the black line is on the tile on the right and not on your tile. it's not your fault.