Vesion 0354 for the map editor is a minor update:
http://knucklecracker.com/creeperworld/mapeditor.php
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-Fixed bug that prevented loading custom background images on the Mac.
-You can set an emitter to have an intensity of 0 now (the previous minimum was 0.1). Note that a 0 emitter actually destroys creeper (it is like a hole).
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