Coconut milk substitutions

You should look for some coconut cream which is a semi solid block of very fine coconut puree found in asian food stores, it's more of a paste. Coconut cream from a can in my experience has been a combination of coconut milk and the "cream" (fats) which seperates out from the milk. Generally a less intensive mixture compared to the paste. In Canada Coconut Cream is tough to find but every store has coconut milk in cans with different amounts of "cream" content which explains the price differences. In the UK coconut cream is a common place item in the asian stores and probably the grocery stores now. ( I lived there in the early 90's so it's probably gone more main stream by now.) Recipes could call for coconut milk, coconut cream or both for curry.

Try to decrease the fat percentage in the custard. Full fat coconut milk has a fat percentage of ~20%, hence the custard has about the same. Fat tends to make the ice-cream more heavy and "creamy". Ordinary ice-cream usually have a fat percentage around 10-16%, and even lower for gelato type ice-cream.

To decrease the fat percentage, add some liquid with low-fat.