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Usually authors of new objects supply zeobjcts.txt. You should use Tools\MMArchive to create a lod, then place all new defs/msk from mentioned maps/packages and rename the lod to xxx.pac. Then place basic zeobjcts.txt in the same folder (Mods\YourMod\Data\[here]) and renamed zeobjcts of all packages you wish to join. Then call Tools\objector.exe [path to basic txt] [path to txt being imported] for each imported txt. Thus you will have joined pac and joined txt for editor.