I would create a folder for all images used on the site. Load your images from this folder, and make sure the folder "travels" to any other computers you have VSD on so it can find the images.
The images you see in VSD's Files folder are basically "snapshots" of the graphic items on your pages.
I would think you still need your original image files saved along with your site.
I've never had any problems moving my sites around, I've copied sites to other computers by way of a jump drive. But I have all my site files in one main folder (including my images folder) that doesn't change, so it's set up the same as the original site no matter where it goes.
You may have to go back to where ever your images are and copy them then make a folder for them on the other computer and re-load them from it.