RR....Does this mean that the CF lower valance is a stick on part with screws, so that it attaches on top of the one piece GTI/ED30 lower spoiler/valance?
If so, it may still fit the ED30 after all 
....I don't know for certain and I don't think Justin (at TTshop) is certain until he hears back from Riso (OSIR). From my own experience of OSIR CF parts it's probably a screw fix to locate but mainly special adhesive. Best you ask TTshop independently because I would hate to inadvertantly misinform you.
I don't know how far proud or not it would be if stuck
on top of the existing lower part of the one-piece Ed30 valance.
The problem is that these are all new parts from OSIR and are new to TTshop too, and we are the first to be fitting them. I'm confident we'll collectively be able to answer our questions in the next few days.
I don't know why VW have changed the rear valance to one-piece for the Ed30 - They could have used the existing R32 spoiler (which looks the same as the Ed30 anyway) and simply had a different tail pipe trim for the Ed30 - Am I missing something? Cheaper on the VW production line perhaps? Definitely much more expensive for the customer (us) to replace - £355 primed. I'll be paying £450 for both my R32 spoiler plus CF tail pipe trim - Just £100 more total.