Thanks for the pics, GGGhost and TheLastAshen!! :rep:
New theory...
I'm thinking the lavender is Weasleys, unlike the movies I don't think the shop would make sense as the first shop you see on the right since it is such a staple, guests would walk right past it so it makes sense to have it a couple shops in. As for the paint job on the windows, I'm hoping it's just an undercoat or maybe these windows will be purple and the front ones will be the movie orange.
I know it's hard to see behind the green cherry picker but I'm sure I see the columns and half round balcony of Gringotts.
I agree that the purple/lavender definitely looks like WWW. My theory for the "?" building is the following...
They obviously had to switch building around, since in Universal's version of Diagon Alley, the Leaky Cauldron has to be inside and to your left (instead of being how we enter Diagon Alley).
Now, if you look at pictures of the WB Studio Tour, you can see a building that looks similar to that "?" storefront (with the shears), but it is to your left when you enter the Tour's set. Since that's where the Leaky Cauldron would go, it looks like they have moved that storefront/facade across the street. Either that store's facade or another one with a similar shape, but they have definitely added a facade between the entrance and WWW, at least compared to the WB Studio Tour.
See 00:28:
[video=youtube;zhWoqobDZXQ]http://www.youtube.com/watch?v=zhWoqobDZXQ[/video]
EDIT! EDIT! EDIT!
Wait, that is
Madam Malkin's Robes for All Occasions and I would think that they would probably make that into an actual store, so maybe that's elsewhere in Diagon, and that's just a similar shaped storefront.
Actually, if you look at 00:14 in the video above, there is another storefront that looks like that (and it's to the right, just like at Uni), but the video is just too low quality and too far away to be able to tell what it is...