You can't import them, but if you have the 184.108.40.206 release you can play them using the Web portion of EW. Please note that any ads will be played (no way to block them) and technically the YouTube Terms of Service prohibits doing this in a commercial setting (and yes a Church is considered a commercial setting).
Another option is to download the YouTube video ahead of time to your computer and import that into your EW schedule. Technically that is also against their Terms of Service so I can't (or won't) go into details on how to do that.
Please note that I am not employed by EW. I'm just a user trying to assist other users when I can. Someone else may have more information or may be willing to go into more details on how to dl the videis.
IS IT POSSIBLE TO IMPORT YOUTUBE VIDEOES INTO EASY WORSHIP?