I would use Decrypter, and then burn with Decrypter.
ISO read, ISO write. Easy as that.
If you have an NTFS file system on your hard drive, let it make one large ISO file. If you have FAT32, enable the MDS split, and let it auto split for you. I would not try to customize the temporary size of the files. (And if you're not sure what NTFS and FAT32 means, ask and I can explain further.)
Just follow this guide, pretty much: