i got the same error message when i start recode in combination with any dvd immediately after trying to import the main movie . it seams to be a bug in nero 184.108.40.206/220.127.116.11 because the older version of nero 18.104.22.168/3.0.?? works perfect.
you can copy the VIDEO_TS folder on your DVD with the windows explorer on your hard disk (any dvd has to be enabled) and then start recode - no error message anymore.
i hope ahead will fix this soon.