i have just tryed to change the default configuration symbols. so replacing the binoculars with a dot, the red line with blue one, etc.
i can select what i wnat and click the OK to close the options box.. but when i click the OK to save the changes nothing happens.
if i click Cancel it closes the widget configuration but when i re-open it the new colors and symbols have not been saved.
i have a few layers that are symbolizing in the mxd and webmap based 'query feature class' aka 'database view'
the symbols look fine in the WAB but if I leave your selection options to use the 'from server' option, i get the binoculars instead of the symbology from the mapservice.
i will experiment by replacing the 'query layer with a featureclass that is joined to the table to see if that option will work.