I had noticed all the NurbsTo rows, then looked up what Nurbs means and realized there's no chance of me understanding what's happening there. I also figured as these formulas are describing where points are, it wouldn't affect the behavior of how the connector wants to land on the outer shape. However I read your response and played with the shape a little more and started deleting geometry sections to see if I could get whatever remains to behave differently. Deleting the top sections until there are 6 sections remaining, the behavior remains the same, deleting one more causes the shape to behave as I would expect any other shape to behave. Deleting from the bottom up, when sections 9-12 are gone, the same behavior, when section 8 is also removed, it changes. Basically the conclusion I'm arriving at here is that it doesn't matter that there are NurbsTo rows in the Geometry sections, but rather the quantity of them.
For some background on what I'm working on, I have been automating network diagrams for a few years now. I like the style of a the icon representing the network device in a box, with text fields displaying the trivia. A previous iteration of this automation used a single box (already a group) with the text fields set up and only needing variables to be set and using powershell, lay out the box, lay out the icon then add the icon to the group. Connections would be made and then the result would require a little bit of layout but overall saving a ton of time. During that time, the shapes I had representing the voice gateway and the UPS caused the weird behavior. I tried figuring it out then but always came to a loss and just accepted that those icons behaved differently.
I'm on another iteration, rather than keeping the network icons separate and grouping them, I've found a way to put together all the icons associated with the box and by selecting an option in a right-click menu, the icon you want to see is the visible one. I use a bit of powershell to assemble this all for me. I'm also using an entirely different set of icons. At this point I have no idea which shape (or shapes) are causing the undesirable connector behavior because their all grouped together (to be able to post something here I went back to the old set). I think in order to pursue a solution as you did, rebuilding the offending shape, I'd have to figure out some automated way to test the behavior of each shape (and each shape's subshapes). I was hoping that someone here might point out that I missed the "xyz" checkbox and that after toggling, all my problems would then be solved. I'd then apply whatever that fix was to the powershell script I'm using and apply that to everything.
Thank you for the response!