Bring the milk to the boil along with all the other ingredients up to and including the sugar, reduce the heat. Add all of the flour at once, stir vigorously with a wooden spoon for approx. 1 1/2 mins. until a smooth glossy paste forms which separates from the base of the pan. Remove the pan from the heat.
Gradually stir in the eggs until the mixture is soft but not runny. Transfer the paste to a piping bag with a serrated nozzle (approx. 12 mm in diameter), pipe 4 eclairs onto a baking tray lined with baking paper, ensuring they are well spaced out. For each eclair, pipe a narrow U shape approx. 12 cm long in one go and then pipe another strip on top.
Bake/dry out for approx. 25 mins. in the centre of an oven preheated to 180°C. Do not open the oven during baking! Then switch the oven off and leave to dry for approx. 15 mins. with the door open slightly. Remove the eclairs from the oven, cool on a cooling rack and cut open.
Mix the yoghurt and lime juice. Dissolve the gelatine in the rum, mix together with 2 tbsp of the yoghurt mixture and immediately stir into the remaining mixture. Carefully fold the cream into the yoghurt mixture, cover and chill for approx. 1 hr. Place two slices of mango on each base. Transfer the yoghurt mousse to a piping bag with a smooth nozzle (approx. 10 mm in diameter) and pipe on top of the mango.
Puree the remaining mango slices with the sugar and water. Coat the top half of the eclairs with the glaze and place on top of the yoghurt mousse.