That could be a little tougher. Lightmaps are saved in the FPM file also and load when you open the level map.
I guess you could try deleting the lightmap files only (dds and Dbo, not sure about the dat files and txt file) in the levelbank\testmap\lightmaps folder after you open the FPM file. then save over the file. ******* make a copy of the files first please.
Running test game then should bring it back to the real time lighting as it should detect no lightmap files.
******* Make a backup of the lightmap folder files, just incase, and also make a back up of the actual map file also. Incase all does not go well.
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