There is no built-in effect in After Effects that goes by the name Double Ramp.
Can you provide a screenshot of the error message?
Two Color Ramp is a Red Giant plug-in.
Is the plug-in on disk, in the After Effects CC 2014 plug-ins folder or other folder where After Effects can see it? Are your other Red Giant plug-ins loading?
OK - thanks! I wasn't sure. I have it in here somewhere.