All links for the map editor are stored in the index.bin file, which is located in data.pak. When you create a new map, a duplicate folder appears: ...\HEROES OF MIGHT AND MAGIC V\Editor\H5MMods\your map. It must contain an empty index.bin file (it is not saved in the map file). You need to put this empty file into some mod to reset the paths, and the index.bin file from data needs to be placed in the map (these files don't work like in regular mods; instead of replacing the old file with a new one, the map editor reads both files). Now, when you create objects in the map editor, they will be saved in the index.bin file inside the map BUT!!!!!! if you save the map, your index.bin file will again move to ...\Editor\H5MMods\your map, and you need to drag it back into the map. If you accidentally forget to do this and open the map, the map files without index.bin will overwrite the files from H5MMods, and all your work will be lost without the possibility of recovery, so make backups after each save. And now, about the most important thing: backups are useful when you bring files to the editor panel so that they can be easily placed on the map. There is a trick here: the map editor considers all files (AdvMapObjectLink) to be the same and displays them in one group, but this is not true - the files for dwellings, castles, heroes, etc. are different, and if you quickly add 20 files without stopping, it turns out that they are all designed for one type, for example, for dwellings, but you needed a castle, 4 dwellings, and 15 heroes, and you will have to do everything again. When you finish adding your objects to the panel, you need to put the index.bin file from the map into your mod