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Test in build as well, bolt still uses reflection, but the live overhead is significant in editor.

Sorry it took so long, lost track of time.
Thankfully this one turned out pretty easy to reproduce on my end.

Create new enum, add elements.
Create a new class.
Create a function graph with a switch on enum for your enum.
Create a game object and add your bolt component and class to it.
Restart Unity, the connections should now be broken.

In Unity theres no guarantee that one Start will run after another, and the same goes for any other event.  If your example showed Bolt's Update going before a Script's Start, then I would say the behavior is off, but from what I see above, it seems in line with the Unity standard.

Bolt doesn't have an Awake, but you can use OnEnable if you need initialization settings in a bolt script before Start.

This is in a flow graph on a GameObject thats in the scene and enabled?

Make a Debug.DrawRay(start, direction) unit.  For "start" get the Ray.origin from the ray you made, and for direction, get Ray.direction * max distance.  This will create a ray gizmo in the scene view that will let you visualize where your ray is going, to make sure it is working.

I would also recommend putting the output of "get collider" into a debug.log(message), so you can see in the console what exactly is getting hit (if anything).  

Just got this bug in some of my own editor scripts.  It seems like Unity changed the default behavior of foldouts in 2019.3

If you need a temp fix until Bolt is patched, you can change Assets\Ludiq\Ludiq.Core\Editor\Inspection\Editor.cs line 590 from

foldoutExpanded = hasContent && EditorGUI.Foldout(foldoutPosition, foldoutExpanded, GUIContent.none);

to

foldoutExpanded = hasContent && EditorGUI.Foldout(foldoutPosition, foldoutExpanded, GUIContent.none, true);

Same here, a workaround is to select the variable directly on the left, but sub variables, like ones on a macro, can't be edited this way, which means that setting the type of a List in a macro is impossible.

Can confirm, got this a few times.  Used the Assign node as a temp workaround.

For me, Unity events fix themselves, but Bolt Events stay "no event" even though they work.