I've noticed a few file share requests popping out of the blog in the last few weeks for various files available for download. It appears that google have changed the way the global file sharing works, and files which were previously available publically aren't any longer. Thanks a bunch google!
I've gone through all the links and republished the files, so they should all be OK now. Looking at the URLs this seems to have mainly affected some of the older file links , as the newer ones are unchanged.
Apologies for the interruption in service!