Out of phase dashed connectors

I am using Draw to create a diagram, with images joined up with connectors. I can have a number of connectors going from one image branching off to, say, four others. The lines, therefore, overlap for some of their length. If I set the line to any dashed style in is very hard to get the dashes to line up, and they end up filling in the gaps. I have tried setting images to whole mm sizes, snapping to grid, using alignment and distribution options etc. Is there a way to do this? Is there any way I can edit the line style to change the dash spacing to a round number, for example?

You can define your own dashing pattern. It is in tab Line Style in Format > Line or context menu > Line. You can determine dash length and spacing. An offset is not possible, dashing always starts with the left dash/dot of the pattern.