I want to create an isolated GND zone on the front copper VCC side. It should be connected to the bottom copper GND side by a plated through hole which is the mounting screw hole for the regulator. So far the result has been an unfilled area instead of a copper fill. Can I do this? (picture shows unsuccessful attempt).
I assume the through hole pad is a separate footprint that you did not add to the schematic? (If it is in the schematic simply connect it there)
If so you can simply set it to have the correct net to this pad.
Similar to what can be done to get via stitching into kicad: