If the whole brush is white then click the clip tool icon several times to toggle the mode.
EX.
______-----
-
-
_____ --GOOD
_______
| |
| |
___|__ |BAD
-
-
_____ --| |
| |
___|__ |+mmm
+pump1
+pump2
+pump3
+pump4
+rot1
Now whenever I actually press the button I get this weird error, then it quits out. Here is a link, I don't own any webspace so I used an old map I uploaded with a screenshot for the image.