Seems to me that the problem here is a general decline in Apple standards (apologies in advance for this anti-apple post but honestly I'm severely unimpressed). Now it's kind of fair that they haven't released a patch for this yet as software testing is a difficult thing. It's also kind of fair (and I think I'm being very generous here at best, this is the point of software testing and it's clearly not just me having this issue) that as this is only affecting some users and they didn't catch it in time.
What really does annoy me though is that I've yet to see any indication that Apple remotely cares that they've clearly created this bug. I raised this bug on the 6th November with them, a good week after I'd already been dealing with this ridiculous bug. Since then I've had one request asking for information (which I've provided) and nothing more. Not even an apology for the issues I've been having. I pay a lot of money for Apple products to not have this problem, I may not make that mistake in the future.
In the meantime, do I lose faith in Apple completely (I'm very close) and just install Linux instead. At least then I'm pretty sure I'll be able to read PDF's no problem, which at the moment is 90% of what I want to do and it astounds me that this is such a problem. I would accept this if I felt remotely like Apple were trying to help, so the Office bug was a catastrophe for them it seems (clearly they know where there market is), they do everything then can to help there. Are there really that few number of people who read PDF's? I doubt it, more likely it's not upsetting business's so why worry. I have never used Office in my life, I am currently writing my PhD thesis in LaTeX and at times it's like bashing (no pun intended UNIX bods) my head against a wall. Pathetic Apple, totally and utterly pathetic.
I also point out that the only reason I upgraded to El Capitan is because my Mac was crashing every week on Yosemite. Apparently it's recommended to upgrade to the latest software early, is it really too much to ask that it might actually work? Well apparently the answer from Apple is twice yes. I'm starting to think Windows 10 may be better, never would have believed that 5 years ago.
Incidentally, for those who want to just read PDF's I recommend Chrome. I know it's not what it's meant for and frankly it s-u-c-k-s (blocked for some reason) but I've never found this crash yet. But then Chrome is not intended as a PDF reader, so some of the other things I like to use are unavailable, for example being able to jump to a particular page in the document instantly. Am I asking too much Apple?