I've never had any luck using dbWaitKey(). Try something else like:
dbLoadImage ("life.JPG",loselife);
while (dbScanCode()==0){
dbPasteImage(loselife,0,0);
dbSync();
}
dbDeleteImage(loselife);
You didn't make a sprite for (loselife), so you don't need to hide it. I personally wouldn't load and delete an image that might have use multiple times in an application..... but to each his own. Also, I don't know if you declared the "loselife" variable with an initial value-- make sure you do that.
The fastest code is the code never written.