This is probably the most frequent issue that I run into with KiCad. Adding a custom image for a silkscreen or copper layer. I don't know why this is always such an issue for me, it sure seems like it should be simple, but for some reason I always find myself fumbling around with it.
To summarize the video, if you've created your images as an SVG file and expect it will be importable (which I presume is the typical way to do it if you want scalability options), then you'd be wrong. KiCad accepts Bitmap images, or PNG, or anything similar, but not SVG files. That's not a big deal, just convert to PNG and you're fine. Make sure the PNG export is a large DPI so your image doesn't get bubbly looking after conversion.
Open KiCad's Image Converter and select Load Bitmap to open your image file. You'll want to select the output format as a Footprint and the Board Layer for Outline as Front silk screen if you're using it as a Logo. Don't select Symbol for this.
Now you'll just need to save the file, don't forget to give it a name because it doesn't automatically move the imported image name onto the new .mod file (at least on a chromebook it doesn't), otherwise, you won't be able to select save. And that will pretty much do it for this tip.
I hope it helps.
This is one of my favorite plugins available for KiCad. It takes your board and reroutes all your traces as curves instead of straight lines. The results are pretty incredible and it makes for a very clean looking board. Another really great part about this feature is if you use a CNC machine to make your boards in house, the machine has a much easier time running through curves instead of making hard 90° turns.