Drag and Drop Widget failing in specific theme

I am new to WP and appreciate any help. I have purchased a theme and installed their plugins. The widget drag and drop does not work when I have one of their plugins installed.

I followed all instructions from the forum for drag and drop to prove it was a plugin.

First they said it was a WP problem, after proving to them it was not. Now they say it is a browser problem.

Is this normal and how do I go about getting this solved in the WP community.

Site not published – just trying to get it published

Thanks for any help – I realize you are all volunteers