I have done some tests of Windows 10 against Windows 7, and I think that the
root of the problem is in that recent-files in Windows 10 is now a bit broken (by design).
The recent-files mechanism in Windows works by creating a link to any accessed
file in the folder
In addition, Each time that a file is selected in save/open dialog-box,
its name is added under the registry key
You can have a look at both places at once, using the free Nirsoft utility
Having looked at the evolution of the contents of the above Recent folder,
I have come to the conclusion that Windows 10 now limits the creation
of the links in the folder.
The file-types I have seen being linked-to are what I guess Windows 10 considers
as documents, which includes file-types such as Word (.doc) and Zip (.zip).
Other file-types than these two are certainly included as well,
but I have not tested more of them.
This new limitation on the contents of the Recent folder is very probably
a performance measure, designed to avoid creating too many links.
A large Recent folder may slow-down the computer.
Cleaners such as CCleaner usually include it when scrubbing clean the computer.
I believe then that there is no Microsoft solution to this problem in
Windows 10. I have looked for third-party products, but found none,
probably because in previous versions of Windows such tools were not necessary.
If you find Windows 10 to be lacking features that you need,
it is easy enough to downgrade back to Windows 7.