Preheat the oven to 180°C/fan 160°C/gas mark 4. Line the base of an 8-inch springform cake tin.
Put the digestives in a food processor and blitz to a fine crumb. Transfer to a bowl and mix in the agave and melted coconut oil. Press into the base of the cake tin and set aside.
Melt the white chocolate in a bowl over a pan of simmering water. Set aside to cool slightly.
Put the cream cheese, tofu, icing sugar, coconut cream and vanilla bean extract in a food processor and blitz until smooth. Gently fold in the cooled white chocolate. Pour the mixture on to the base and smooth it level. Bake in the oven for 1 hour and check. Bake for another 10-15 minutes if still not set. Turn off the oven and leave to cool in the oven for half an hour. Remove from the oven. Cool completely, then chill for a minimum of 4 hours, or preferably overnight.
If icing, beat together the vegan spread and icing sugar with the vanilla bean extract to create a smooth buttercream. Use around a quarter of the icing to skim the top and sides with a thin layer. Divide the rest of the icing into 4 bowls and colour each a different colour. Cut the ends off 4 x disposable piping bags and fill with alternate colours. Pipe rows of different coloured dots around the side of the cheesecake.