Grapez, The only thing I can suggest is that you send me a copy of your .rmf (the simple box one) and a copy of your lights.rad file. I set up a test map like you said, and it worked. I know how frustrating this must be....
Do you get any other errors when you compile? Are you using ZHLT 253 1.7? You might as well send the compile log as well.
It might be an idea to register on this site as well....