I had the "This is embarrassing ..." msg yesterday, but it seems to be resolved - I just kept trying - must have been on the Microsoft side.
I updated my apps though the Store (beta) - 10 apps - a few that I had uninstalled.
After installing all 10 updates I tried to launch Mahjong and it did not work - I don't recall if it was updated or not.
I logged off and back on and ran the Store (beta) again. 'New' updates were available, so I updated those 7 apps.
Two failed with 0x80070002 errors (I think that was the error code) - I tried them again and both eventually updated (retried update 2 or 3 times for one of them)
The Store (beta) would not update ...
Anyway, according to this:
Unable to update Windows Store apps in build 9926 - Microsoft Community
the Store (beta) requires Apps to be auto-updated. I think it's a punt, but I manually changed:
AutoDownload = 2 on the key below to the value in Sharath Srinivasa's reply
AutoDownload = 4
Did it work?
Not on this machine. I have not restarted the machine, and will update the thread after I do a restart later today.
edit: Restart had no effect - changed key value back to 2.
DISM re-register and DISM RestoreHealth also had no effect. RestoreHealth had many reports re: languages ... oh well, time to wait for the next drop.