Current questions and answers regarding the map editor.

Okay, there might be a few options. Perhaps you forgot to click Export in the list of files on the left due to inattention. Changing the file extension to something else (wav or mp3, ogg is not supported, I just rechecked, I apologize for the inaccuracy) might also help. If the editor still can't "handle" it, send it to me, and I'll try to upload the file myself.

I think I did everything as you described. I clicked New in LoadingScreenSound, created a file called Test_Stinger.xdb. In it, I unchecked Is3D, and then tried to load the sound in SrcName; it's on my desktop in mp3 format. I select it, but the editor doesn't react. That is, the xdb file appears in the map, and the index.bin was initially there (but then it disappeared for some reason), but the sound doesn't load into the map. And I don't understand what you mean by Export.