Fixed issues relating to File chooser causing an error (Perhaps java version could cause such an error?
Removed a JNI library that would not work on certain Windows systems and put a more efficient method in its place and removed some of the code associated with it (It was literally used only once and not the best way to do things...)
This VLC Skin Designer 0.8.7 should be runnable for most java versions now without issues? If you have any issues report them in the issues.
For this jar (not the main branch though) I have also added the /lang/ files within the jar itself (to avoid language errors) and testing your skin should work now.
To run the jar make sure you have java downloaded (https://www.azul.com/downloads/?package=jdk#zulu)
You can then either double click the jar file or typing in to the terminal "path-from-inside-zip/bin/java" -jar "path-to/VLCSkinEditorAndDesigner-0.8.7Dev-All-Libraries-Runnable-Jar.jar"
You can learn how to actually use this at https://www.videolan.org/vlc/skinedhlp/ and https://www.videolan.org/vlc/skinedhlp/basics.html
Perhaps you can even improve an already existing skin. You can find pretty good themes as an example to learn from on Github (new themes eg https://github.com/dmtiir/VeLoCity-Skin-for-VLC) or the VLC website (some old themes) and can open the ".vlt" files with this program and edit, improve or make your own.
You can put your themes into VLC by enabling custom skin in preferences and then placing .vlt in C:\Program Files\VideoLAN\VLC\skins and then restarting VLC and then seeing a new "Select skin" on interface when right clicking the window and then pressing the .vlt (perhaps the one you placed in the path, restart to reload the list etc)
Enjoy this fixed version of the program and remember to report any bugs! :)