There are a whole host of errrors in this version. True bugs. There are other conversations on the TOC problem so you are not losing your mind - Apple did when they put out a poorly tested product.
Hyperlinks are now 'link' and do not work in PDFs. The problem with links is when you edit them in the new little box that appears. If you type the URL and let Pages creat the link itself, that link will survive to the PDF. The second you edit it - i.e. add a shorter visible name. or try to copy a URL in to the box, or even 'add link" to existing text it no longer works.
This may not help with TOC but at least I was able to inlcude some links (albeit long ugly URLs) in my PDF document.
There are also problems with layers and text wrapping. I'll have a text box nicely wrapping around an object, then the next time I open the file the text is not wrapping at all and is in front of the picture. AND even though it shows correctly in Pages when I print to PDF the text is wrong again. But then when I reprint to PDF it's right. I also have layers that automatically move to the front again and again.