I've also had problems after test running 4.5.0 on my 1903 machine, but I always create a system image first to restore with should things go awry.
I've reported to Shane the adverse effects it had on my machine but as he's 8hrs behind me, it may be a few hours before he sees my email, but I'll report your problems to him as well.
I've opened a thread with a warning to create a system image before running the repair program - unfortunately you hadn't seen that before running the repair program.
If you open the repair program and click on Backup Tools you will see the top option to restore the registry.
Click on Restore and then on the Registry Restore tab and then use the dropdown to click on the dated restore then hit Restore Now.
Can you also check to see if you have any restore points which you can revert with if that doesn't resolve.
Restore points don't normally have any effect on Docs, but it may revert the registry changes that have lost your docs.