When I bulk edit books, is there a way to set the rating to 0 stars/ remove all stars?

(just leaving the setting as '0 stars' is not working)

Calibre 0.63 but I had this problem in all other versions too I think.

Good call. I just tried it and sure enough no worky

I just created a ticked (for the first time in my life, hope I did that right ;) )

Yay, just upgraded to 0.6.37 and this is working now!