More than just the combo installer needed
I always use the combo updater.
I had all of the difficulties you mention at the end of the article. Mostly had to do with anything that does heavy network usage.
The only solution that worked for me was to download Maintenance.app from titanium software (titanium.free.fr) and run *all* of the steps, then reboot.
Then remove my user caches (~/Library/Caches/*) and my Mail caching folder (~/Library/Mail), which Mail would recreate when I restarted it.
After that lot, I had no more trouble. I suspect there was some inconsistency between versions of cached data somewhere.
Anyway, the above steps have, thus far, always sorted out such issues...thus far.