FaytOcean

In case anyone is still dealing with this problem, I was able to fix it by running nmm as admin. Instead of it not copying files to the data folder, it places shortcuts to the files located in the nmm repo. I guess the engine can use the links to load up the necessary files on start-up, which is actually really great, since it saves a ton of disk-space! But bottom line is you should always try running as admin before taking more extreme measures.