As you upgraded from 12.2 to -current, you are strongly requested to read file CHANGES_AND_HINTS.TXT
There are topics relevant to X and input devices (keyboard, mouse) and to the change to kde4:
Speaking of Xorg, the version of Xorg shipped with Slackware 13.0 will not
(in most cases) require an /etc/X11/xorg.conf file at all. Configuration of
input devices and such is handled by HAL, and the X server autoconfigures
everything else. You can still create an xorg.conf file if you wish, or you
can create a minimal xorg.conf with only the specific contents that you wish
to override (as an example, to use a binary-only video driver).
Due to removed drivers and other such changes, it's quite possible that your
old xorg.conf will not work correctly with this version of Xorg.
Due to the upgrade of kde from 3.5.10 to 4.2.4, you will need to move your
existing $HOME/.kde/ out of the way (either completely remove it or back
it up somewhere else if you think you might need it again for whatever
reason); otherwise, you will almost surely experience odd configuration
problems with kde applications.
Unfortunately file UPGRADE.TXT
is not yet updated for the migration from 12.2 to 13.