DVD Cloner VI is not a program that is commonly used around here. In fact, I've not heard of it. It could be part of the problem.
Memorex media is not well regarded in these forums, not by most of us. We recommend Verbatim and Taiyo Yuden as reliable blank media, with Sony as a third possibility. Choice of media is very important for consistent results.
You might try slowing the burn speed down to 8x when using your Memorex disks. See if that helps.
+R or -R doesn't matter too much anymore unless you have a fairly old dvd player. Then you might need to bitset +R disks, or just buy -R blank dvds.
The two programs that are updated frequently to deal with new encryption and protection schemes are AnyDVD and DVDFab. You should try their trials. AnyDVD is just a decryption program, but works well with free programs like DVDShrink. DVDFab is a complete backup solution, and the decryption/ripping section of DVDFab will continue to function even after the trial expires. But the free section is no longer updated quite as often as the paid version.
Once the trial finishes for DVDFab, you can still use it to rip dvds to the hard drive. Then use DVDShrink to reduce the size of the movie if it needs to be done. You can find DVDShrink here: http://www.videohelp.com/tools/DVD_Shrink
To burn to a disk use ImgBurn, a very well respected burning program that is also free. There is even a version of DVDShrink that uses ImgBurn automatically if you wish. It is found on that download page I linked.