I am having similar issues. version 1.0.1 worked fine but am anxious to get the awesome seach capability and better buffering for NMT and PC with this latest version. I followed (I think) the instructions from the link that Martin just provided. Downloaded ffmpeg.exe and installed in C:\ffmpeg\ffmpeg.exe. Setup the YouTube.xml manually.
Here's my log files. Any help will be very much appreciated.
Playlists on this plugin would be stellar !