Tiling that can be seen in your first pic happens because the area designated for the picture used doesn't match (sometimes tiling is very usefull though, like in large background for example).

example:
you have ID field that is width="100" height="100"
and you have a picture that is 50 pixels width x 50 pixels high
Four 50x50px pictures fit into 100x100px field => tiling

k thx