You must install custom widgets manually in MashZone NextGen.
The installation requires a widget zip file, which is located in the PPM installation directory.
<PPM installation>\ppm\server\bin\work\data_ppm\MashZone_NextGen_BA\customWidgets\<WidgetName.zip>
Procedure
<MashZone NextGen installation>\apache-tomcat\webapps\mashzone\hub\dashboard\ widgets\customWidgets
This creates a custom widget subfolder, for example, functionFlowWidget.
The PPM custom widget is now available in MashZone NextGen.