Looking good Mike... tis quite the process just to craft clothes no matter the app, but yes indeed, thank goodness for extract tools...

This type of extraction has always been an option within Wings3D...

Just select the faces desired and use extract command... then as it is a closed object, just tweak to desired shape, include any hem rings, then select the leg faces, and the waist face, do a intrude to desired thicknes, select new edge rings, cut and connect, do a bevel with resulting loops and you are finished same as posted example

Whats the process within ZB3?