Unfortunately, I tried putting those details into "Reference Data" as a base mod... ...but that didn't work (I got a glitch where the player setup would only let me choose the small map, as the left and middle buttons were gone (all the other mods work fine, so it's something in Reference Data...
This actually sounds like you were using outdated files
The reference data is updated for each patch release in the downloads section, but that is the base fileset for new mods.
The mods use the same folder structure as the stock game does. That is, if your mod is called Test and you only modify values for ships, the only thing you'll need is the GameInfo folder. But if you modify any strings, your mod will also need to have the String folder with the modified English.str. If you do any work with textures (including the game's 2d graphics), your mod will need to contain the Textures folder with the modified files, and depending on what you do the Window folder as well.
The Textures folder is special in that it is the only one that can exist in a mod with *only* the changed files. All the others (GameInfo, Window) must have *all* the files in them to work. So if the only thing you change is one ship, well, you still need all the other 800+ entity files in your GameInfo.
Hope this helps a bit. If you have any more specific questions, feel free to ask
