I have the software now to follow the building instructions but there seems no way to attach the red arm assembly to the larger yellow module other than an axle pushed horizontally into a round hole. It just falls out. ???
That’s exactly what I found when I built it and I gave up in the end. The problem is that LDD simply can’t handle projects this complex and just leaves parts out. As you undoubtedly noticed, it also assembles parts in impossible orders. I’ve just about given up on GBC modules with .LXF instructions.