Both NI and IK Multimedia plugins are a bear to install/manage. This is why I normally opt for freebie plugins that come from companies that don't charge. There are plenty out there which work well. My favorite delay plugin is Bionic Delay from interruptor. I have plugs from both IK and NI, and I do like them, but it's almost a crapshoot as to whether when I turn on the DAW the plugins will show as registered or not. Hassle.

-Scott