Kernel updates are something that slackroll
handles better (IMO) than slackpkg.
slackroll's user interface is more painful to use than slackpkg.
It may not matter, but you should check your /etc/rc.d/rc.modules symlink. I'm willing to bet that it isn't pointing to rc.modules-3.2.45.
(I say that it probably doesn't matter because I just checked mine
and it's pointing to rc.modules.3.2.45. I'm running 14.1, so that should be pointing to rc.modules-3.10.17. I'll be changing that symlink a couple of seconds after I hit "post".)
(And, no, I'm not using slackroll on this box. I'm starting to wish that I had.)
NOTE: I just did a diff on rc.modules-3.2.45 and rc.modules-3.10.17. They are the same, other than what I had manually changed in my 3.2.45 copy. That's probably true between the two rc.module versions for Slackware 14.0.