Paul, this is incredible! Thanks for sharing and making this resource available!
I’ve been re-creating your mind-map into a family tree, and got nearly all the way done setting up the formulas until I hit a snag on my “DB Items” table (mine is named “People”) on the “Draw line to parent” column. Was wondering if you’d mind taking a look at what’s going wrong? The situation is that in this formula for the “Draw line to parent” column, I’m unable to make a connection to the HLP Chart table to target the URL Encoded column:
If(thisRow.[Parent item].IsBlank(), "", Format([Connector line].URLEncoded,
thisRow.[_X center], thisRow.[_Y center], thisRow.[Parent item].[_X center], thisRow.[Parent item].[_Y center]))
Here is a gif of what I’m experiencing as I write the formula:
Unsure of what I’m doing wrong here 
happy to provide you editing access to the doc I’m working in if you’re up for the assist (which I’d greatly greatly appreciate)! I’ve got my fingers crossed that the fix is small and obvious. Writing formulas like the one’s you’re using in these tables is well beyond my skill level, but thankfully I’ve been able to re-create everything successfully (as far as I can tell) up until this point.
If I can get past this, the only other ask I have kicking around is how to go about drawing horizontal connector lines between two items where only one has a parent. In my family tree use case, this would be used for partnerships/marriages.