@roxics I’ve experienced this exact issue myself. I used to edit on FCPX and it would have been so much easier to just swap out the watermarked file with an all-but-identical non-watermarked version. When you replace it with the shorter audio file found in the zip, it doesn’t work, and you have to re-cut the music all over again, which is annoying, to say the least…
If you’re editing on FCPX, there is a work-around if you have an audio file editor. Audacity will do the job and it’s free. This only works if you have only used sections of music from the first version of the track found in the preview. If you’ve used bits from the other versions, it gets a bit more complicated.
The idea is, FCPX is looking for a specifically named .mp3 which is of a certain length. So what you need to do is change the shorter file so that it has those same attributes as the watermarked file that you’re trying to replace.
For instance, an awesome track which I purchased a while ago by @lifeplanetearth (I hope they don’t mind me using their track as an example) has the main 2:20 track and they’ve included three different 10sec loops, so the preview file is 2:50. The preview is named 3D20549376_technology-ambient_by_lifeplanetearth_preview.mp3. The first thing to do is open it in Audacity. Then you can add an appropriate amount of silence to the end of the track to make it longer than the preview file. in my case, I’d add at least 30 seconds. 40 just to make sure. It doesn’t have to be exact. As long as it’s longer than the preview, FCPX can use it. Click ‘export as mp3’ and give it exactly the same name as the preview. Now replace the file in the FCPX library, relink and your good to go.
If I did happen to use some audio from one of the three loops, I would have to re-build the preview by pasting the 4 separate audio files together in Audacity in the same order that they are in the preview, but this is only guaranteed to work correctly if the author has constructed their preview file without any extra gaps in between the tracks, but I’m sure that in most cases that won’t be an issue.
I think @add9audio might have the better solution though by simply asking the author to provide a watermark-free preview mp3 for you. I know I would be happy to oblige and I’m sure many other authors would too.
As for why Envato don’t allow us authors to put what you need in the purchasable zip, I can only guess. Maybe they don’t realise how useful it would be and they are trying to save some server space. I feel your frustration.