First of all thanks for your quick answers. Ok I'll try DVD+R DL in the future, but now I have 5 Verbatim DVD-R DL and considering their price I'd like to make a good use of them. After reading what you said I understand that there is still a way to make it work by rebuilting the ISO with a correct layerbreak position. I tried something like that before creating this thread, I decrypted the ISO into FILE (VIDEO_TS Folder) and I rebuilded the ISO with the ImgBurn Build Mode following this guide http://forum.imgburn.com/index.php?showtopic=1777 , the problem was the same.
So can you point me to the correct direction for rebuilding the ISO, a guide would be much appreciated, thanks.