For some time now I have had the following problem. The automatic (or manual) update doesn't work.
Yes it does, but you must have the current version of the *updater*, which can only obtained by installing the Stand-Alone Addon Manager, or installing any of the products using their current installer. This because the we changed one of the Live Servers, so your old updater is still going to the one which is not used anymore now.
Act window: The scenery that the file model.cfg is not installed (seems to me an incomplete sentence)
Act window: Python support file KDEN\_init_.pye was not installed.
None of these messages have any relationship with the dialog box that says there was a problem updating files, that caused by the fact your updater program is outdated, as explained above.
And none of these are "errors", they are just messages on the progress bar, indicating that, since you don't have a product that is going to be updated, that update will be skipped.