There is no need to partition the drive to make two images. An image is just a file (a large one!)
Images are.tib files - you simply call them different names when you create them.
"When I read back the relative partitions and try to open an individual folder...."
I don't understand this - an image is just a file, the only folders are compressed inside the file.
You can't "read back" a partition - what exactly do you mean?