To join two fills, select the first one click one edge with the fill tool select the "+" from the pet pallette and trace the second fill with the magic wand! Don't forget to erase the second fill. Repeat as many times needed. Can't think anything else now it is quite late here...
ArchiCAD 22 4023 UKI FULL,
Archicad 21 6013 UKI FULL, ArchiCAD 20 8005 UKI FULL
iMac Retina 5K, 27-inch, 2017
4.2 GHz Intel Core i7
32 GB 2400 MHz DDR4
Radeon Pro 580 8192 MB