I have curiousb's neighborhood defaults, and for some reason the road and sidewalk don't appear correctly in lot view. I placed everything in the folders I got from downloading the radiance and seasons bundle in Downloads.

Read the #3 message as described on the site:

3) The road replacement by itself does not appear on the section of road in front of a lot in lot view. So, you need to cover the Maxis road somehow. As a solution for this I have provided a road overlay mesh and recolours for the different sections of road. [...] The road overlays are under Deco>Misc in the catalog, and they cost zero Simoleans (so should be at the very front of the catalog). You will need to use the 'moveobjects on' cheat to place the overlay.

This will happen to most road overlays.

Roads are also not very happy with being changed, so if not done properly they will occasion switch back to the original road when you reload the lot, just to give you more work. I can't remember if there is a fix for this or a method that stops this from happening, but there probably is.

Okay, thanks!

There are a lot of files in CuriousB's .rar - it's easy to get confused as to which ones you need. In your main Neighbourhood_Bundle .rar file, there should be another .rar file that says RoadOverlay in its name. You need to extract the files in that into your downloads folder and then use the moveobjects cheat to place them on your lot as in instruction # 3 copied in simmer22's post.

There's another .rar file in there with Sidewalks in its name. This appears to contain floor tiles that match the sidewalks on CuriousB's roads.

This is how all road defaults work, in hood view, usually with floor tiles to cover the road in the lot.