I have tried several versions 4.x.x (both 32 and 64 bit) in Windows 10, including the most recent 4.3.1, but I never got the file links working as they should:
F7 does not find the file related to the current entry.
Ctrl + Shift + F7 searches for a very long time but does not find any links. (Apparently it also keeps running after closing the program, because I had to kill two instances of the JabRef.exe process using task manager in order to be able to uninstall the program.)
Each time I have had to return to 3.8.2. This is quite annoying, because if I saved the database in 4.x.x, the group tree is gone in 3.8.2 and I have to restore the database from a backup.
Any suggestions how to make it work?