Well, yes, that’s amazing. Definitely works. It now looks like this:
The only issue I have now, is that if the bullet point I’m currently at - now referenced and highlighted by the active relationship line - has more than one line, the relationship line does not reach the ‘bottom’ of the block - as shown in the screenshot. Otherwise it really works like a charm.
I bow before your skills! 
No, seriously: thank you.
Edit: Should I remove the ‘solution’-label so that we can have this topic open a little while longer?