For the fritters: Boil the pumpkin until soft and easily pierced with a knife, about 15 minutes. Remove from the heat and drain well. Allow to cool.
In a large mixing bowl, combine the cooled pumpkin, flour, 2 tablespoons sugar, salt, milk and egg. Mash with a fork until fairly smooth.
Heat the oil in a large heavy-based saucepan over high heat until it reaches 350 to 375 degrees F. When the oil is hot, carefully drop in spoonfuls of the batter and fry until cooked through and golden, flipping once.
Remove the fritters with a slotted spoon and drain on kitchen paper. Repeat until you have used all the batter.
In a bowl, mix the cinnamon with the remaining 2 tablespoons sugar until well blended. Dust the fritters generously with the orange zest and cinnamon sugar.
For the ginger yogurt: Mix together the ginger syrup and yogurt until smooth.
Serve the warm fritters with the ginger yogurt.