If the set of skipped packages (probably same for files)
defined by the configuration exception panel is "too large"
up2date will generate a warning message window (... packages
are available but were not selected ...) that exceeds
the height of the screen.

The "OK" button (to continue) is at the bottom of the
warning message window.

Depending on the user's choice of window manager, it may
not be possible to move the warning message window to
expose the "OK" button so that the user can continue
with the up2date process.

It would be better if either (simple fix) the "OK" button
were at the top of the warning message window rather than
at the bottom, or else (fancier fix) if the list of
available but not selected packages was an embedded
scrolling list with the warning message window sized to
fit the available screen real estate (or something
similar).