Hi
I create simple audio files quite often.
it seems that you are nearly there. when you have a single file, add it to the stat section and it will work fine. just click on the green ok symbol. and you have created a sound file (not a folder).
After that, it's just to click add sound and drag the new file over from the "eigeneBibliothek"
And then map it to a function, and for simple sound files like this, "momentary Function" mode, is recommended in most cases.

In the window, you have open you can click on different folders, and get instructions for different types of sound files.

Sometimes I also use an audio tool to shorten, clean, and/or amplify sound clips etc. (non Märklin files) I use the free audacity, but there are also others.

Thanks for all the help.

I had 3 sound files to download to the mSD/3, they were Flemish station announcements.

The main point to remember in the process is it has to be two step.

Firstly create a 'start.wav' file from your own souind wave file in the mDecoderTool.
Then save the project, exit and take your own file out of your directory that has both files.

The start.wav file needs to be on its own, to transfer into a P key function in mDecoderTool.
Otherwise you get file format error messages.

Also with each extra sound file, rename the source directory for each file load, otherwise they overwrite.

Other than that it is pretty straightforward.

best regards
David