Ok I have built with your suggested compiler flags above:
https://www.pisd.co.uk/peds/download...install.tar.gz
I can't help feeling this is not going to help much. If the installer elf runs fine (those errors you mention are normal. Linux has many menu systems and the installer tries to update a selection. You undoubtedly will not have them all installed on your system) without an illegal instruction error then its unlikely to be the wrong CPU instruction set causing the problem. I think we may have found a legitimate bug, either in the game or ones of the libs you have installed.
I don't suppose by any measure of good fortune you are near the south of England are you? (starting to think a hands on approach is needed) If not how do you feel about setting me up a ssh remote access login to you system? A chroot jail will be fine as long as you copy gdb/gcc and /usr/include /libs etc...