I was in EW6 an extra long time (2-3 hours) double checking after what hopefully is my final conversion before going live. When I was checking a theme using Inspector and received the following error. I can say it's an error I haven't seen before.
over 2 years ago
Does not have to be long session - I got this error message within 30 minutes when I had to access and assign a theme to each and every song.