MEP System Browser isn't very useful: it just reproduces ducts structures (why pipes aren't considered as well?) but it doesn't allow you to reorganize your systems.A System is arranged in many branches (the one served by Heat Pump n°1, n°2, etc): I ...

In case of a large duct (1320 x 220) the elbow curve is too large: factor radius can't be set less than 0.6. It seems that Archicad reads the widht as it were the height and sets the curve consequently.