I'm sorry you are having so many problems.
I think I have had every error possible with this program and finding "work-arounds" has only led to other problems (especially with ver 6.4)
After battling and losing countless hours trying to get this program to work properly, I have finally decided to move on to adobe encore.
For me, Encore can do everything Dvdit does, seems much more reliable and has popup menus.
Unfortunately, you have to buy encore as part of a package with premier etc, which makes it expensive. But when you consider the amount of time wasted trying getting bluray to work with Dvdit, the alternative seems more attractive.
Best of luck