User blog comment:Amrosa/Beginning Update 6.3.0 with 3,607 Gold/@comment-31776838-20180602235239/@comment-28169398-20180605070455

The code for Column 6 is doing a format validation. In this case it was set to integer, so by putting in percent, it view this as an error (Red text).

Off the top of my head, I don't know the code if you want to change the validation format to %.