So it;s been a few days and no more replies , any ideas or anything I can try??
IF IT WERE ME... I'd compile the lot from scratch ON the hardware we're having issues with which
should help ensure the processor being used is forcefully supported. Being that it's old hardware, expect it to take a while to complete. If there are issues the compiler can't figure out, it'll point you in a close direction of why. Start with the library that's throwing the Illegal Operation (webkit and/or wxwidgets) and use extensions for everything else for the beginning. For each package you compile yourself, create your own extension (filename.tcz) and replace the one in /etc/sysconfig/tcedir/optional with your new one.
Content for creating extensions is readily available both on the forum and wiki.
If compiling isn't in the cards for you, I'd recommend trying Debian out and see if their existing, though old version of boinc functions on your machine "at all." Yes, it'll likely be slow... but if the Manager screen comes up, it indicates potential that it "can" be done on your hardware, but how efficiently is another story.