If I select a file and it's signature and select to Verify, a new window open, but this window remains blank and Kleopatra just hangs. I left it there for a long time and it never completes the verification process.
I already tried this with several files (including gpg4win-3.1.10.exe and gpg4win-3.1.10.exe.sig), including files that I have verified successfully in the past.
Here you can see the print-screen of Process Explorer, showing Kleopatra just started gpg.exe, but short afterwards it's killed (the red indicates it's being killed), on the side is the Windows miniature of the Kleopatra Windows, where you can see the Verification window remains blank:
I am running Kleopatra on Windows 10, latest version, just updated a couple of days a go.