In LR 5.3, my keyword panel will no longer work when I click on the panel. The only way I can enter a keyword is to click on command+k to activate the panel. I cannot add or delete in the panel once I have entered a keyword. Does anyone know how to restore the keyword panel to its original fucntionality?
First try to relaunch Lightroom / restart your computer.
Optimizing the catalog could also be worth trying, if you haven't done so recently.
The next thing to try is to reset the preferences.
You are also not running the latest version of LR5 - use Help > Updates, or download the latest version (5.7.1) from here: