I have images on a portable HD that were altered with my LR laptop application and now want to bring those altered images to my tower computer LR application as altered on my laptop. Is there a way to do this?
With the HD connected to your Laptop, select the desired images (or the desired folder or the desired collection) and the File->Export as Catalog. (Do not check "Include Negatives")
With the HD connected to your tower computer, open Lightroom, select File->Import from Another Catalog and point to the catalog created by the instructions of the previous paragraph.
Retrieving data ...