I recently bought a 2013 imac......I have the photo shop/ lightroom 5 from the web on my laptop........Now I also want it on the imac.....downloaded lightroom, no problem but I want my old photo catalogs on the imac also. How do I do that?
First find the catalog, then copy the entire folder for the catalog to the iMac. Here's a tutorial http://www.orchardviewcolor.com/node/249
The bigger issue is making sure the catalog on the iMac can see the image file. You might be better off moving the catalog and all of your images to an external drive, or a network drive, and then accessing it from either computer.