Hi, I too have the same problem, Global Exclusions use to work until the latest version which is Version 8 were used.
I think I may know the reason for the bug.
For example:
I've added 'C:\justatest\file.exe' in the global exclusion area using 'C:\justatest\*', this works before the update, now it doesn't, it will still detect it as virus when i try to copy it somewhere else.
I went in to the Virus Chest and found that file.exe in the list, then I notice the Original Location was odd, instead of showing 'C:\justatest\file.exe' it shows '\\?\Volume{djkf8sj7-55tg-fsd3-45ps-sjd89hfh9}\justatest\file.exe' instead.
So I went on to try adding '\\?\Volume{djkf8sj7-55tg-fsd3-45ps-sjd89hfh9}\justatest\*' in the global exclusions and viola, it works now.
Hope this info helps.