Jeronij and fellow Mac users,
I think I may have figured out a way to get the V2 walls to work on Macs. Using File Juicer, all of the files in the V2 walls package have some kind of file folder structure in their filename. (Example: JRJ BSC New Concrete Walls Modern 1R\AA01 DW Cemento V1 1X NAM Lateral V22X_5142c943.SC4Lot)
The slash indicates that this file (AA01 DW Cemento V1 1X NAM Lateral V22X_5142c943.SC4Lot) should be included in a folder (JRJ BSC New Concrete Walls Modern 1R). I think this is how .zip files create their own folder structure when unzip-ing.
To make a long story short, I created the folder paths for all of the .SC4Lot files, changed the names of the lot files to only include what was after the slash, and moved each file into its correct folder. Magically, it worked. I now have the V2 walls in my Misc. Transportation menu and they work just as they should.
Someone else should check this to make sure I'm not some fluke. Also, I did not have to edit any of the .SC4Model files or the .dat files. Strange.