[Graham]

Just looking through the rules, I see that "universal chassis" are allowed, but can't see them mentioned in any of the "Construction Awards" categories.

Does this mean they are only eligible to gain points in their "Event", but can't gain any for their position in "Construction" type?

By convention I have always associated the plastic Universal chassis in with the 3d chassis construction cars, and it was not an intentional omission this time. So yes they will be included in with the 3d chassis constructed cars. 
These construction awards will be attributed at the end of the series, not in the same manner as with the Triple Crown Series.