Why can't I download youtube videos into my ipod using Ares Tube?

I have the Ares Tube program and have gone through all the settings to make sure its correct. I've selected my videos and when it's done downloading, it automatically pulls up the iTunes program. But when I look for it on the iTunes, it's not there. I go to my c: drive under the Ares Tube download file, and it is not there either. I've tried multiple times to download videos and each time it states the download is 'done' but each time I don't see the video in my ipod. Thing is I used this very same program in the past (as recently as four weeks ago) and it has worked. I have been able to download at least 15-20 videos but now it suddenly does not work! I've even gone so far as to delete the program and downloaded it again. Can anyone please tell me what could be the problem?