Rinse and finely grate the radishes. Rinse, peel and core the apples. Cut into quarters and grate finely. Combine the yogurt with the radishes and apples and mix with sugar and salt.
Thoroughly rinse the avocados. Cut in half, remove the pits and hollow out. Dice the avocado that was removed. Mix with lemon juice and 1 pinch of salt. Rinse the cucumber and dice. Peel, core and dice the small apple. Mix the cucumber, apple, crab and dill with the avocados. Fill into the avocado halves.
Use the cucumber slices and toothpicks to create sails on the avocados. Arrange the avocados on the salad.