Dear Sean,
As we spoke 1 week ago on a other post : https://answers.unrealengine.com/questions/93011/421-build-error.html
I have posted what you have requested.
I have tried yesterday to package the same project with the last version 4.4.3 and I had the same error.
So I tried few hours ago one last thing before giving up. (I have created a blank project and copied my blueprints only and few personal assets) And I was able to package the game !
I really think that the issue could be linked with the “Free” assets from the store. I have downloaded few of them and some of error messages into the compile log was about texture not found etc… (But it was properly in my project folder…)
Anyway, I will try to continue what I did and will use my own assets. I hope that I will not get a error again if I have to package my project one day. (It could be really frustating if after months of work you see that you cant do anything about what you did because the project cannot be packaged without more detailed reason…)
Thank a lot for your support