I've been using the Now Playing widget for a long time with spotify with no issues but I think since the last version of BetterTouchTools, It kind of act weirdly..
When spoify is running it works fine but if I quit spotify it just stays on the last played song like if it was paused. Then if I click on the widget (usually to open the app) nothing happen.
If I manually open the app, I have to click play on the app to refresh the widget to show the currently playing track and be able to play/pause the song.
I've tried (with the new beta interface) to add a second widget to see if it was the same issue and it was! I then deleted the last widget I've created and the grey box stayed there even if the widget is not in the configurations anymore.
So now I have Now Playing widget not really working and an annoying grey box doing nothing next to it!