This has the entire mod broken into modules as the original Tinholt version was, and includes the empire update that adds hundreds of new pictures. It is the same as The Great Exhibition on steam (download/subscribe to that one if possible), but is broken into modules for anyone who has difficulty downloading a large mod file like that regularly or needs a local version. When updating (until the event window breaks again) you can just download the Empire Update file as it has all recent changes to the pictures.
To install, unzip contents of TheGrandExhibition.zip. This will give you 7 .zip, and 7 .mod files. Put all 14 of these files in your Documents\Paradox Interactive\Europa Universalis IV\mod folder.
If you deleted this after you installed 1.29, just create the folder again and put the mod in there. The mod will appear as "local mod" in the new launcher.