Trouble Making a Custom Siren

Hello, Noodle the Goat here (does not stand for Greatest of All Time),

I've been having trouble making a custom siren mod lately.
Some steps I've taken would be following this tutorial and downloading the few zip files included.
https://www.beamng.com/threads/how-to-make-your-own-siren.55715/

Despite following several tutorials, downloading people's tutorial files, I cannot seem to get this to work properly. I zip the file, rename it to "custom_yelp", go to Beam.NG in my documents, use the linked file folder, and place it in "Appdata / Local / BeamNG.drive / (current version) / mods / repo".
I've even tried to put it into "Documents / Beam.NG / mods / unpacked", the "old fashioned way", and still, nothing seemed to work.

Strange enough, I downloaded...
https://www.beamng.com/resources/uk-emergency-vehicle-sound-pack.3730/
...unpacked the mod, only tampered with the audio files. I replaced two files. "uk_siren.wav", and "uk_yelp.wav". I replaced the two with my own, renaming both to the same "uk_siren.wav", and "uk_yelp.wav". Same wav and stereo format, respectively. I tried to trick the game into playing my sounds with a mod that was set up in a way that worked. Mind-boggling, it broke the mod!
> What the scallop?

I don't know if it's just a skill issue or a problem relegated to just my computer, but I've been real stumped trying to figure out what's going wrong! If anybody has any ideas of what's wrong, please tell!

Many thanks in advance.
~ Noodle the Goat.

P.S. The borked mod is provided below. I don't know if it's just me, but if it works fine for you, I'll try and download the game onto a different PC, and check back with the results later.

 

Update to Original Post!!!

I know people probably aren't going to see this, but if you do, I have found a solution.

First and foremost, you must download a source from either of the links. You must open it not with file explorer, but a file explorer program like 7Zip (Free), or Win-Rar (Paid, but then again, who has ever actually bought Win-Rar?). Open the file, place yours into their art/sound paths respectively, then you can save everything from said program.

In other words, the program is used as a 'protected' reach into the file without somehow messing something up like the encoding of the zipped file. If you want to know more, it won't matter if you respond a year after posting, I'll be happy to respond with a step-by-step!

~ Sincerely, Noodle the Goat. (Commonly referred to as Noodle the Fox, or The Somewhat Fantastic Mr. Fox. )