Widget author here. I think you just have a dot where it shouldn’t be. Class to apply should be:
with no dot/period.
Also make sure the column is named NUMBER. That is, the “name” property of that column should have the name that you put into the “Column Name” field of the widget.
Indeed issue with className :)
You should add custom class name to the place where you want to use it.
I can assume that “Class to apply: .text-info is wrong”, because in place where you want to use it it’s just empty(“null”).
So try to put your own class and change in place where it should be used.