A light with a brightness of 1 has certainly no effect.
It is currently at a range of 6000. When i set the range to 1000 the whole thing gets darker. And i can of course make it smaller to get an even darker look down to black. So there is effect.
Besides, your level is so bright you won't see much effect by lights anyway.
The current brightness comes from this one light. Which shouldn't cast light at all because it is nearly black.
Only existing Light is at 0/0/1, Map ambient is at 0/0/0, Sun light is at 0/0/0. Fog is at 0/0/0 each. No more setting there to make it darker
A piece of advice: Often people post their beginner's problems to the bug forum and then are surprised when the posts are moved straight to a beginner's forum by a moderator. Of course, bugs are always possible. But a bug would affect all users, not only you. When you see that the other users can create beautifully lighted levels, ask yourself what might be the reason that you can't. I won't know because I have no info about your level aside from the screenshot, but you have all information and should be able to ask other users the right questions.
Above all, read the Game Design tutorial. It's several years old, but the basics of doing a simple level including lighting haven't changed.
Thanks for the advice
