Yes, you can install NickelMenu. I've attached a text file to this message to be copied to the nm directory on your Kobo after NickelMenu is installed (.adds/nm). Once NickelMenu is installed and before you toggle the screensaver, on your Kobo's exposed storage, open the Kobo directory inside the .kobo directory. You will see a file called Kobo eReader.conf. Open that file with a text editor and look for the [Feature Settings] header. If you find that header, insert the ExcludeSyncFolders line under it, otherwise add both lines below.
Code:
[FeatureSettings]
ExcludeSyncFolders=(\\.(?!kobo|adobe).+|([^.][^/]*/)+\\..+)|(screensaver_old)