Earlier I started editing the campaign maps (the prologue, to change the tileset to Sunken Ruins and to give Kul’tiras Marines a canon-correct team colour), but after an hour spent fixing up the map, I tried to save and discovered I could only save the file elsewhere. This was frustrating as my changes worked really well.
My suggestion would be to add some functionality to the World Editor to allow someone to edit campaign maps, but have a backup version of the map in place. If the player then wants to restore the campaign map to vanilla after making changes to it, they can.
Well you have to save somewhere… How else is World Editor meant to know where you want the map file to be saved?
This is kind of pointless. One can play the maps individually outside of the campaign feature and in any order one wants. The only reason one would have to use the campaign feature is if achievements were involved, like with the StarCraft II campaigns, in which case they need to be modification resistant to prevent people cheating the achievements with maps like “all campaign achievements”.
Generally if you press to “save” rather than “save as”, a program will save over the file you opened. In this case, when I opened the campaign map, pressing save just causes it to try and create a new map. I didn’t try to edit the campaign map to create a new one, I wanted to edit the campaign map itself and use it in the campaign.
And the idea isn’t really pointless. I was editing the campaign maps so that I could play through the campaign with those changes, not to play the maps one by one separate from it.
Personally, I don’t care about achievements, they aren’t something that interest me at all, so perhaps a way to prevent misuse would be to have it so if a person modifies a map in a campaign, then they cannot complete Achievements for that specific campaign. It would then allow players to modify the maps if they wish, but prevent people cheating the achievement system.
You opened an internal map which is part of the game data. That map is not a map file. Hence it tries to make a new map when one tries to save. StarCraft II works exactly the same.
Directly modifying the game data is not recommended. Warcraft III uses CASC which is not designed for such modifications as it is a cache of data from a CDN.
One might be able to edit the campaign map files indirectly via local files if that functionality still works. One would want to try and overwrite the various parts of the map file with your edited ones.
I am not sure anymore. There used to be a registry setting that enabled local files. Loose files put in the WC3 install folder would then be picked up and processed by Warcraft III as part of the game data. When they moved to CASC it still kind of worked but I am not sure if that is still the case.