To fix "loose leg syndrome", I use needle nose pliers. Insert the tip of the pliers inside the aluminum leg. Prying the handles open forces the tip of the pliers against the inside of the legs. Keep rotating the pliers placing them wherever the legs are dimpled inward from the leg sockets. Using this method you can reshape the leg end back to a round shape.
Sometimes, even using this method a leg will still be loose or slip out of the leg socket when the kettle is moved. You can then jam a very small finishing nail between the leg and the leg socket. It works as a shim and will solve the loose leg problem. Place the nail to the inside of the leg so it will be less visible.
I've used CLR to soak ash pans that have that concrete like ash buildup had any problems with it harming the aluminum. You may still have to use #0000 steel wool to clean te ash pan after soaking in CLR. As @JEBEV suggested above, look at the WKC Home Page for cleaning tips.