Thanks for the reply Cameron, I did download the G5 version and unzipped on the Mac’s standard unzipping program. The other stuff in that article is too advanced for me to figure out.
Thanks again though,
I don't have any other suggestions for you if you are unable to verify the download with those instructions. That version is the one I'm typing this reply to you in.
An urgent security update has been made available due to an issue fixed in Firefox which we are mirroring. You can try downloading that and seeing if the issue recurs. If it still happens, I'm going to have to insist you check the download's integrity first to rule that out as a cause.