Why can't I install LibreOffice 4.3.7.2 on my Mac OS 10.7.5

According to the system requirements, version 4.3.7.2 should work on my Mac OS X 10.7.5 MacBook. But when I want to open it, it says that the program requires Mac OS X 10.8 or later. I downloaded the 64 bit version here: Index of /libreoffice/old/4.3.7.2/mac/x86_64
Any ideas?

It requires Gatekeeper to be set to “Identified Developers” or lower during installation. See my answer to Q64923 for fuller information.