No the recipie actualy has gelatine. I think that she added it to the juice she extracted from 4 oranges. and boiled it up. I think she would have pored it into a cake tin to 1/4 inch and let it set. She woud then place it on top of the cake.
She definatly used fresh squezed orange juice and the recipe called for gelatine.
For thouse of you who don't live in the UK. A chocolate company based in York made a chocolate orange. Chocolate flavoured with orange. 2 years ago they sold the recipie to poland and the recipie got changed. to see what they are and what she did by placing the segments around the top of the (now covered in chocolate) cake...
If anyone thinks it would be improved in anyway by using marmalade but this uses fresh squiesed orange. for the chocolate coating prior to putting the terrs orange slices, she heated up some crem and added chocolate buttons into it to melt. so it was a mixture of chocolate cram and maybe something else ???