I find that if a bulk tool is selected, you should wait until it is finished loading before checking the boxes. Otherwise, you can check all the boxes and when you come to the bottom of the page it is like your browser is crashed. However, if you wait when first selecting a bulk tool(check and make sure you can see the bottom of the page) everything works just fine. That might have to do with my paltry wind-mill powered internet speed of only 50mbps, over in the US you guys are probably measuring your speed in GB or TB I don't know.