Form is related to Shape. Cast is a type of Shape. Cast is a synonym of Roll. Roll is a synonym of Drift. 
Complexity is a type of Quality. Complexity is derived from Complex. Complex is similar to Complicated. Complicated is the opposite of Simple. 
Form <--RelatedTo--> Shape <--IsA-- Cast <--Synonym--> Roll <--Synonym--> Drift 
Quality <--IsA-- Complexity --DerivedFrom--> Complex <--SimilarTo--> Complicated <--Antonym--> Simple 