I also installed Slackware 13.37 and found KDE to be difficult. It has some kernel requirements that are not documented, like an experimental kernel security check.
Try it with a distribution huge kernel and see if you get the same problems.
On my Slackware 13.37 I have switched to using xfce4. It will use many of the KDE tools and sub-systems without getting the whole KDE experience (recreation of Windows features).
You should also check two 'features' that KDE starts automatically. Unless you see some need for them, they just bog the system down. (AKONADI comes to mind, but I am not sure right now)
One tries to index all your files in preparation for a quick search. This can be turned off in some control menu, but I have difficulty finding it again (and I don't have my notes here).
Cannot remember exactly what the other was, but it was not such an immediate problem.
More like, "what do I need that for". It also has a background server.
I finally brought up the start-up menu, where systems are started on KDE boot, and removed the servers for those mis-features.
Trying to un-install them has its own problems. I un-installed, and re-installed, one 3 or 4 times, and finally left it installed, but disabled.
I recommend xfce4, at least until get solutions.
I made a copy of the startx script that starts xfce4 instead, and called it startxfce4.
Problems with KDE on Slackware 13.37 are bad enough, that I still run my Linux 2.4 system
for daily work.
Last edited by selfprogrammed; 04-09-2014 at 06:19 PM.