I downloaded Adobe Creative Cloud with Photoshop CC and LR CC. I can open Photoshop CC by just clicking on the PS icon in the app section of CC. Nothing happens when I click on the LR icon. Both programs indicate they are up to date. I have LR 5.3 on my computer and it works fine.
I have used the Adobe Creative Cloud Cleaner Tool to remove both Photoshop CC and LR CC and then reinstalled, but only Photoshop CC works.
Can you launch from Program Files (or Applications on Mac)?