Just by way of an update from me
I still get the odd "Something happened" message even when making sure to run the media creator in admin 'mode'.
But on the W7 front with the fubar'ed Windows Update, having exhausted all the fixes and methods I went back to basics and did a Restore back to 10th May when according to the 'update log' I was AOK for WU to work.
So following the restoration WU worked and I was presented with approx. 45 updates (oh, forgot to add I altered the WU settings to not download but notify as I wanted to have control over what & when downloads took place!)
Now I made written list of the updates and the publication dates and progressively updated in small lots of offers based on the publication dates..............I was fairly sure the rogue KB update was in the ones dated 12th May. To cut a long story short I was checking that the list of installed updates was present after each "step" and lo & behold at one particular step trying to download the 9th June updates it errored out with 8007370B but before that the installed list was there to see!!!!
So I restored back to position just before 3 of the 12th May updates and all OK so looked at those updates more critically and there was one that MS Info was that it was to update and cure a WU issue plus that in itself could cause an update issue but advice as to how that self resolved on the same page. As a test I installed that single KB and the problem occurred so IMO this was proof positive...............a quick restore and back to good times with progressively the rest to the outstanding updates installed but still in blocks to trap any recurrence tot he problem.
The rogue was KB3020369 - the April 2015 serving stack update for W7. The telling info as far as I could work out was that "the servicing stack is included in all Windows installations" so all being well not installing this little pain in the posterior will not give rise to other issues further down the road.
So hopefully not famous last words it is now OK and in my researches I found that KB3035583 when it comes down the WU channel (will it be the next Tuesday one?) will deliver this update for "Get Windows 10 app" for Windows 7 ???
For now I am pleased that W7 should be OK and hopefully well behaved at least in regard to WU