In a large zip top bag use a rolling pin to crush tea biscuits. Pour into a large bowl. 

Add coconut, sugar and melted butter.  Mix well. 

  Press crumbs into the bottom of a greased (8-inch) tart pan. Place in fridge while preparing filling. 

Blend or process mango into a puree.  Pour mango puree into a pot, add sugar.  Mix gelatin with water until dissolved.  Pour gelatin into pot, heat over low heat until sugar is dissolved. 

Whip cream until stiff peaks form.  Fold into mango cream.  Pour filling into chilled crust, shake to spread evenly. Let set in fridge at least 2 hours or overnight.  Serve with more whipped cream if desired.