It does look a great recipe, in fact I think I'll make one also. Glancing over the recipe the only points that I can see are
10g/�oz sultanas, soaked in water and drained
I would suggest leaving these to soak overnight
3. Bring the milk, double cream, salt and vanilla pod gently to the boil in a pan.
4. In a bowl mix together the eggs and sugar until pale.
5. Gradually add the milk and cream mixture to the eggs, stirring well to amalgamate. Strain into a clean pan.
As eggs set at a relatively low temperature, if the milk/cream mixture is anywhere near boiling when it is added to the eggs/sugar paste there is a fair chance that the mixture will be cooked or partially cooked which is not what you are looking for. I would recommend only heating the milk/cream mixture until just before it simmers (wispy steam rolling over the surface of the mixture).
I like the idea of the crossaints.
kind regards
Parson Snows