The fuel leak might just be the return lines deteriorating. They are generally cloth covered and run in a daisy chain configuration from one injector to the next and then to the fuel return line. It should still be fixed though. Clean up the area and see if you can tell if it's coming from the injector itself or where the return lines are. I just replaced these on my 83 240D. The return line hoses are cheap and easy to fix. They just push on. I overpaid for mine at 12 bucks for 18" at the dealership, i'm sure phil sells it here cheaper.
For the shake i'd check the engine mounts. If it only happens at one rpm spot, thast's got to be it. Also some people have commented that a broken air cleaner mount(yes!) can cause an awful rattle.

Dale 240D