For your question Cat2, instead of a predefined list just use a constructed list using Unverified Perl in the logic. For this example, I will assume the name of the list is 'Cat2List' currently and that Cat1 and Cat2 are single response questions. I am adding all 8 items of Cat2List. Then adding item 7 if the answer at Cat1 was 7, otherwise adding item 8. So the list will always have either item 7 or 8 but not both. Hope this helps.
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