There is no way back, but to remove the symlinks and copy things back to the default place.

The script fetches the folders usr/share/icons, usr/share/nokia-maps, usr/share/fonts, usr/share/locale, usr/lib/locale, var/lib/apt, usr/share/themes, var/lib/dpkg and /var/cache/apt and copies them one by one to the second partition of the internal card (by default 2GB) and creates links to the new place for the system to find them.
Basically you move folders from the smaller rootfs to larger optfs.