Hello ronmilne,
Usually the quickest way to find out what may be causing your project to fail when packaging is to use the Find function (ctrl+f) in a text editor program to search the log file for the word “Error” and “Warning”. From doing that with this log, this error came up:
ERROR: Windows SDK v8.1 must be installed in order to build this target.
Can you please install the Windows SDK v8.1 from Microsoft’s website, restart your computer, and then try again? If you receive any more errors, please let me know and we can try to figure it out.