I have decided to have a go with graydiant and made a CTF map and I am using CODUOMaker to compile the map. During the compile process the returned light settings are default i.e. Sunlight 1, Ambient 0 which differ from my worldspawn settings. Why is this? All the worldspawn settings I have used are taken from a standard game and I know they work. Because the values returned are default the map is pitch black until you look directly at the sun. Have I set up something wrong with the CODUOMaker?
I am using build 101b1057.

Open your .map file in Notepad and check if the settings are correct.. sometimes Gradiant doesn't properly save your worldspawn settings when exporting your map.

Also, check your compile log for errors.. some errors make the lighting part of the compiler fail.

This is not a CoDUOMaker issue, that's just a frontend program for the stock compiler.

Wow this is old but now I've run into it. My worldspawn settings in my map file are correct:

"ambient" "0.1"
"sunlight" "1.0"
"classname" "worldspawn"

but in the compile I get:

sunlight 1
ambient 0

There are no errors in the compile and I'm using the same batch file I've used for all my other maps so what gives?

This is one that has caught me many a time. Simply add the line:
[key] _color [value] 1 1 1 (note the US spelling of colour, underscore needed as a prefix)
to the sunlight and ambient. By doing so when you compile the map you will see your ambient at your setting rather than the default 0.
I also noticed that sometimes when you want to make a tweek here and there to the worldspawn settings the new values wont go into the Entity Dialogue box. If that happens close the application and restart then have another go, you may find that willl help.