Have set up 2 ftp connections through windows explorer. They will not work from Dopus, they do work from windows explorer. Have also used the dopus ftp to set up connections which do work in dopus 
Is there a way to hide the Network Locations Group in 'This PC' folder ?
I don't think there is a way to hide them currently.
(Also didn't think anyone would actually use File Explorer's FTP support with any other FTP client installed. )