Have you tried updating from your windows start menu?

"Can I ignore them and work without them as long as I don't have to go back and amend anything?"

I don't know about you, but the odds of me needing to go back to the program to work on a client file that far back is somewhere between slim and none.  If your odds are about the same, I guess I wouldn't lose a lot of sleep over it if updating from your start menu doesn't work.