Having just updated to 6.1.3 non-beta today, I hit the same prompt as it looks like others are getting, but I think I know the issue.
The problem, it seems, is that you moved where it's looking for scripts. Before this update, there was no scripts folder, and subsequently no folder created. I tried moving the mounting/unmounting files there, but that's only part of the issue. The install is also not putting the rc.ProFTPd file in scripts either (it's not saved anywhere in the config folder). So any of those files can/are throwing errors.