You can reattach an arrow that is going from one variable to another by grabbing the arrowhead and dragging it to another word.
For example to change the connection from orders booked to cash flow into a connection from orders booked to sales receipts you could just drag the arrowhead from cash flow onto sales receipts.
You can reattach the origin (start) of an arrow by selecting an Arrow tool, clicking on the variable you want to start from and clicking on the first handle in the arrow you want to redirect. In the above example clicking on sales receipts and then the arrow handle would remove the link from orders booked to cash flow and create a link from sales receipts to cash flow.
