Do you have these files on your computer?
They come from the xkeyboard-config-1.6-noarch package...

Yes, I installed those files, and it made no difference. The exact same errors. Why would it make a difference?

For the X server to function correctly, it's best to have all the packages from the 'x' series installed.

OK, I installed them all, and everything is exactly the same.

What could be causing this error, and why?

Also, why does everything in x/ need to be installed? I also wondered why there were no individual package descriptions, other than $thing is a part of X.

But do you still get the xkb errors in your log?
Check if you see any other lines with (EE) in them.

Yep, still the same errors, and no other lines with EE.

I don't think install all the packages helped..., I still get this error, and I was not lacking any functionality beforehand...

Could it be something to do with keybaord maps or something? Even though all my keys work fine individually...

Volunteers wanted --to write and maintain ~300 slack-desc files for X!! LOL
Good luck finding enough info to know what each package really does, or what programs might need it...

Where did you get 300 from, and why do you think that info would be hard to find?

I am not asking for or think it is really needed, but it would not be as ridiculous as you imply.

I'm not on a box with newer X, so I'm not usre of the exact number of packages in X, but I do remember it is well over 200. And you are right that it is not ridiculous -many of the descriptions are pretty generic -like each *proto* package simply provides the headers for compiling the corresponding library. And the driver packages are pretty self-explanatory -each dealing with a certain kind of hardware. But provividng any useful info about each library and font package is a little harder because -many of them don't provide any useful info in the sources.
Actually, someone did make a big effort to provide some more descriptive desc files for some of the packages here:
http://sourceforge.net/projects/slackx/

OK, I have fixed this now. I reinstalled all the xkb* packages, and now it works. How odd.