Hi Gumbanomicon,
I have not implemented any drawing functions for down arrows. You are right, there needs to be atleast one depth between parent and child node for an arrow to appear. The easiest fix would be to move the nodes Hail Storm, Refresh and the other node that starts with "Se" one to the left (increase the depth by 1).
I'm still thinking about adding more drawing possibilities, but that will be a huge task to undertake.
Did you know that you can copy paste your Techtree.json content into the Techtree JSON Output field (it only shows [] when you open the editor). Then click the "Update Form" button above it. This will load your tree for more editing.
Alternatively you could search the Techtree.json itself for the header lines (like "header": "Restore") and then the depth number will be above that.
Best regards,
Felski