I have alot of settings too. Just sometimes going from one major FW version to another and loading the previous configuration introduces problems as some of the newer options don't reflect in the old configuration. Also the configuration file could be corrupt in some way just enough to carry over the problems seen in the last FW version.
I've never heard of any exporting of the settings from the router to XML. You might try to view the routers web page by turning off your browser Styles then see if you can export from there. Not sure if that will work for you or not.
Helps to take screen captures of each page on the router for reference though.
I know what you mean, which is why I had reset the router, applied all the FW upgrades first and THEN started setting it up. So all my saved config "checkpoints" were AFTER all FW upgrades were done.
Yep, I used to use screen caps, but now I use copy/paste into MS Word because I can then copy/paste back the settings. Less typing.

Yeah, I've turned off the styles before to get ALL the settings but it's actually less messy to just copy/paste the normal screens to be honest.
So the problem is back already since my last post. So resetting and reloading my saved config did NOT resolve this. So I'll do the reset next but configure it manually and see what happens. Ugh...this is making me regret I bought this thing. Thank goodness I have 30 days to return it.