I was able to create a Windows App yesterday at the publishing portal. Today I tried to create another Windows App and it failed. The status is Failure. I edited the Windows App yesterday and resubmitted and it also failed. Has anyone been able to create a Windows App today?
The App Builder team did check the logs yesterday and said that all failures they had were because of the issue I mentioned in the other thread. Strange that you had one of three platforms with the problem though. I'll mention it to the team again on Monday. Glad you got it built though!
If it still doesn't work for you tomorrow please send me your project ID so I can ask the App Builder team to take a look. You can find the project ID by hopping over to the Content & Layouts tab and then looking in the URL (it's the long string of letters and numbers, a.k.a. the GUID) in the middle of the URL.
Your issue is almost certainly the one in my linked post above. Please see that post for details, and try again after about 30 minutes. Hopefully the fix for that will be deployed soon (it's in one of our sister teams so somewhat out of our control, unfortunately).