uchisen.com uses python scripts remixed from maurimo to generate the animated .svg files. Original kanji .svg files provided by the KanjiVG project.
If you really want to generate your own animated .svgs, I'd highly recommend you go to the original project and download it there, as that's set up for general use and provides great documentation on how to use it.
But, if you still want to use this for some reason you should create a folder "kanji" at the root of this project and add any .svgs you want to convert there.
Run run_script.py to change all kanji in the kanji/ folder into animated svgs.
Running delete_extra_files.py script will remove all kanji not found on uchisen from the kanji/ folder.
Python scripts are formally released under MIT/BSD (at your option). You are free to do what you want with this program, please credit maurimo's work if you use it. If you like these animations, please give a donation using their github page!
Original .svg files provided by KanjiVG project licensed by Ulrich Apel under the Creative Commons Attribution-Share Alike 3.0.
To comply with the share alike license I've made all derived .svgs available here (found in the animated/ folder) also available under the CC BY-SA 3.0 license.