I'm not quite sure what you're trying to do now, but if I understand you correctly you want to open the file, but have it show up on the screen (and over your normal windows) transparent (i.e. have no application window/titlebar/etc), is that correct? If so, I don't know of any program. I was suggesting importing it into GIMP, editing/positioning it within a larger transparent image (in GIMP), saving it from GIMP to another PNG file, then using it in MixEmergency.