The following is a list of known issues with MATE on Slackware:

Wed Mar 27 04:23:24 UTC 2013
If you have dual monitor with NVidia card and set it up to use both monitors
as separate, you might encounter some freeze lockup.  A temporary workaround
is to change it into TwinView in your xorg.conf

Sun Mar 24 02:47:56 UTC 2013
If you run into strange panel issues, or missing icons, or theme problems,
please consider backing up or clearing out some of the hidden directories in
your $HOME, like $HOME/.config and $HOME/.cache and $HOME/.local.  If you
switch back and forth between different desktop environments, sometimes those
settings can get polluted.

Fri Mar 22 16:44:59 UTC 2013
Help menus and help buttons do not work -- this is a known issue per a MATE
upstream developer and scheduled to be fixed at some point but not in the next
release (1.6).

Fri Mar 22 16:43:36 UTC 2013
Working to determine whether mate-polkit is necessary.  According to upstream,
it is, although it results in duplicative polkit actions when a USB stick is
inserted, for example.  Disabling polkit-gnome in the "Startup Applications"
is a workaround until more testing is done.