Good game only got a 4/5 because of the annoying restart button not working when a girl or you die. Here is a tip I used to get 3 stars on some lvls if the map has stars on the background use them as references for your shots. Move your mouse over one and shoot if it gets you a kill remember it. Then take your next shot form another star that you think will get you a kill if it doesn't work restart and do it again. This is what got me through "Behind You" and some other lvls that has stars on the background. Always try to get kills that cause them to fall on a trap like the saws. Getting 3 stars isn't that hard only lvl 37 gave me trouble.
The badge info is where the chat is it under a tab called achievements. Seem that they moved them there which is a better idea cause it saves space on the page