DVD Shrink is not the best option to make an ISO file to burn on a DL disc, because is not able to place correctly the layer break. This explain the error you get in ImgBurn.
The best option is to use ImgBurn instead. There are two possibilities:
1) Make an ISO of the entire original disc and then burn the ISO with ImgBurn. In this way you'll have a 1:1 copy of the original disc.
2) Use DVD Shrink to remove undesired contents, and then save the re-authored disc on HDD as files (not as ISO). Then, use ImgBurn to make the ISO or burn directly in build mode on a DL disc.
The procedure depicted in point 2 is perfectly safe (I did this many times), but if you are in doubt, I have a solution :bigsmile:
After you re-authored the movie using DVD Shrink, save all files on HDD. Then, make the ISO with ImgBurn and save it on HDD too. Finally, read the ISO file with VLC player, and check results. If everything is good, you can burn the ISO on a DL disc