Place gelatin in a small pan, and soak in 1/2 cup of milk, allowing the gelatin to swell and soften. Stir once or twice as it sits.
Into your blender, put remaining ingredients and blend under everything is well mixed. Be carefully not to over-beat so you don't turn the whipping cream into butter.
Heat the gelatin and milk over a low heat and stir to ensure the gelatin melts. Slowly mix this into the blended mango mixture and blend for 20 seconds again.
Pour into 8 half cups and let it chill for an hour or two until set. At this point, you can top with additional chopped mango, or add whipped cream. You should also be able to unmold these carefully although I'm not that talented.