I followed the directions in the FAQ for telling K-Meleon
to use a proxy, but it still doesn't do it. One thing I
noticed is that the FAQ says to edit all.js in a directory
called prefs under \program files\k-meleon\defaults
but after installing, I just had a directory called pref,
not prefs. So I made a prefs and copied my all.js there
too, but it made no difference.

Maybe it's some strange syntactical thing? I have lines like
this in my all.js:
pref("network.proxy.http","192.168.1.12");
pref("network.proxy.http_port",3128);
I've tried the proxy IP's address with and without quotation
marks, and have tried hostname instead of IP number, but
nothing helps. I just know I must be doing something
stupid, but I can't see it.

Any suggestions (other than "pull your head out")?

Hey, there's no problem! If you've already really read the FAQ, then you have to know the answer Well, it doesn't matter that you have manual proxy settings in an other browser, to get it work you need changing the next lines:

pref("network.proxy.autoconfig_url", "192.168.0.1");
pref("network.proxy.type", 1);

These are my settings, just change them in your 'all.js' file to yours and let the other lines as you changed. It should work.