ROIs are pixel based so they can only be restored on images that are of the same dimensions and pixel sizes and the images should be co-registered to each other. You can use Reconcile via Map to convert an ROI using map coordinates. This converts the pixel coordinates to map coordinates of the original image and then tries to reconcile them to the new image. If the two images are not well registered to each other, than the conversion will not be accurate and you can have the ROIs shifted. I would check to see how well the images are registered to each other for clues as to why the ROIs are not well placed.