I'm trying to build up a predicate that can work on multiple tables, where I have a particular entity.

The code I tried was:

IRelationPredicateBucket predicatePreviousEntity = new RelationPredicateBucket((entity.Fields["parentId"] == entity.Id));

Which it doesn't seem to like. What is the equivalent which would work?

The field indexer returns an IEntityField2, you should do:

IRelationPredicateBucket predicatePreviousEntity = new RelationPredicateBucket((((EntityField2)entity.Fields["parentId"]) == entity.Id));

Fantastic, thankyou! I knew that it'd be something easy that'd make me feel like an idiot

Brilliant product, btw.