Hello
you need to what you suggest
"ALL" = select none value
"ALL" = select "contest", "no contest"
-- finally you can have a button "clear" that clear ALL values:
<span class="fc_delall_filters"></span>
.fc_delall_filters {
background: url("../images/delete.png") no-repeat scroll 0 0 transparent !important;
...
}
so you can replace the "delete" image with your image
1. notice the "body" below to make it of higher importance
2. notice: MY_ALL_IMAGE.png
body .fc_delall_filters {
background: url("../images/MY_ALL_IMAGE.png") no-repeat scroll 0 0 transparent !important;
...
}