When your campaign runs and it says “DPRK air defences fired ROK aircraft.” even if your scenario is in europe, this means you need to edit your strings.idx/.wch files found in the campaign directory.
Load up WitchFix and first you need to select is the .txt file or you get error. Then select the strings.wch file in the correct campaign directory. Now click Wch → Text button to convert it to text format. Open the new text file it created and then you can edit the strings. Leave WitchFix open if you tend to just quickly edit and try the changes right away.
You should replace like DPRK → Iraq or something like that, what ever is necessary for your theater's campaigns. When you are done, just save the text file and then switch to WitchFix and click Text → Wch button. Now you have brand new strings.idx/.wch files created the in the chosen campaign directory.