Here is what you do:
1. Open the project in Unity
2. If you haven't already, download the Universal Windows App plugin
3. Convert to IL2cpp (in my experience it gets converted better than .net)
4. Create a build in a folder (before you do make sure it is master instead of debug(
5. Double click the solution file.
6. Click on project tab, then scroll down to store (make sure that it is master instead debug, and x64).
7. select sideload option
8. create x64, this will create appx file as well as dependency
--------------------- MERGED ---------------------------