You might find my code in nominalized_clauses.py useful (which you can find in my branch (kphowell)). I followed what Joshua did in the negation library, so you can look there too. Lines 5-18 in nominalized_clauses.py check to see if a nominalization feature is on any of the lexical rule types and if it is, a nominalized-lex-rule supertype is added to the supertypes of that lexical rule type. Then I can define that supertype based on the nominalized clauses choices.
If that’s what you’re trying to do and you have follow up questions, let me know!