Well, simply open the designer and generate using the Adapter Template Set Group.
Maintaining your custom code at partial classes facilitates things. Then you have to do some refactoring with the differences in your custom or GUI code, for example:
- IEntity2 instead of IEntity
- Some predicate objects receives an EntityFactory object in Adapter Template.
- In Adapter the filter generally is an IRelationPredicate bucket, in SS you pass IPredicateExpression.
- Obviously it could be that exist breaking changes at your Business/GUI layer (the way you fetch/save data).
- Due to LLBLGen design, migrating the Validators and Auditors is pretty easy.
In general and in my own experience, this is easy, though it depends upon your actual design (of course).