I wanted to remove outside walls of Grid Map but I couldn't find the correct file name to do that at the editor (too much TSStatic or something), how can I do that and also make it a seperate map without messing anything?
I believe you can just go in the world editor, and click on the wall. It will automatically select the object. If you want to make it a separate map, the easiest way would be to copy-paste the whole level and rename it to something else. ( copy Steam\SteamApps\common\BeamNG.drive\content\levels\GridMap.zip\levels to Documents\BeamNG.drive and rename levels\GridMap to something else) You can then edit the info.json to put another level name to be able to see which level is which in the level selector.