Quote: "I have my project on "mygame.fpg" and i don't think i have modified it at all."
That could just be it. For some reason FPSC uses a set ambiance level for all levels in your built game (Unless you add some scripts to change that).
If you want the ambiance level to be the same on all your maps, then edit the "mygame.fpg" and change the ambiance in the "Global Script" under the "Level Settings" tab. Remember to press enter then Ok too apply it. Re-check to see if it changed. Then exit FPSC and open it again, then re-do the test game.
If this doesn't work, then create a new .FPG file and make all the changes you want for the game and add all the levels but don't build it. Click Ok instead. Re-load the map you added into the build setup and test it to see what happens now.
This at least works for me, my ambiances and even my hud and fog remains un-changed during test game.
Hopefully this works out for you and good luck...
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