General question now that there's a substantial balance patch incoming: is it possible to open assets that have already been modded?
When I tried to use the editor to open a previous mod to look at the changes made, the editor gave me an error. I think it said the file name didn't match? The thought later occurred to me that it might have worked if the mods were the same name as the original file, but I didn't think about that till later. Even if it did, it seems easier to compartmentalize changes (and therefore troubleshoot and customize) if you have differently named files for separate classes or such within a mod folder.
I can kinda understand why it doesn't do this currently, since you have the different bundles linked together in order for the changes to propagate across the proper bundles. But it seems like having to re-modify every change after every patch would be frustrating.
I don't have a great answer for this, but it's something to think about with the huge numbers of changes coming in 1.1 for balance purposes that people are already saying they want to change/revert.
The quick answer is, depending on the mod file you want to edit, if the modded objects all belong to the same vanilla file, renaming the mod file to the respective vanilla file's name will let you load it into the editor.
If the modded file contains objects which belong to different vanilla gamedatabundle files, you should either split the objects into different files and load them separately, or load the same file into multiple Load Data screen forms.
The editor currently checks the filename of the file you are loading and determines which database to fill with the file's data. I know this shouldn't work like that. When I fix it, there will be just one Load Data form, which will take all kinds of files, and will recognize the objects inside by their $type property, and load them in the right place automatically.
When I began work on the editor, I didn't yet know that the game doesn't care about the name of the mod file, nor that it isn't required to separate changes into different mod files, if these changes apply to different gamedatabundle files, i.e. that you can group changed objects that belong to a few different vanilla files in the same mod gamedatabundle. I thought modded objects were required to be separated in their own properly-named gamedatabundle files which match the vanilla names.
Due to this confusion the Load Data screen works the way it does now. I will rework it, but I have a pretty big roadmap of changes I'd like to make first. The general order of priorities is: things that currently can't be done with the editor, then things that can be done, but require some manual work, then quality of life features, then improvements to the styles and layout, which also need more work.