Theres nothing wrong with that archive AFAIK.
Its the Installer app you have, thats probably outdated.
Check in your "SYS:C/" and "SYS:Utilities/" which Installer version you have.
If its older than 43.3, replace it with the one present in the P96 archive. (even if it sound strange, seen that the "Setup.info" points to a simple "Installer" without path as default tool)