Hey,
I was reading the forum and dropped in some of the installation issues i was also having.
The trick in the beast is the number 5 and it’s position for some of us.
Since my gear is offline most of the time, and since i am interested in updating things i started downloading things. I didn’t want the 10.5 yet, allthough i was going to buy it, but not yet. But i looked after the latest update for nr. 10. That is 10.05.
Sadly i downloaded without being aware of it the version 10.5 and then things went berzerk. 
No licenses for padshop pro (that i have), licence issue here and there, …
But in fact it should be cataloged as an user error, since with the update your system is being upgraded (for all versions) to the next version for vsts too.
In the end i have installed the updated 10.5 and not the 10.05 wich i was looking for.
If you get this type of issue, well that is the problem. Roll back if you don’t wan’t to update to 10.5.
For me, I just jumped on, since i was going to do it, and ok now i’m on 10.5. So it is…
No problems thus far. But no checks made is also true.
kind regards,
R.