Not getting observeField (or observeFieldScoped) to firing callback

If the code you've shown is a copy and paste then you have a typo:

m.exitDialog.observeField("buttonSeleted", "onButtonSelected")

Should be buttonSelected.

But that's not the only problem.  Even if you fix the line, add a print in front of it and I bet it prints out false meaning the statement failed and your observer will never be called.

print m.exitDialog.observeField("buttonSelected", "onButtonSelected")

That "buttonSelected" needs to be attached to a component.  I'm not sure how to accomplish that; I've only ever done it via an interface alias in the XML file for the node/group/component or whatever it's called.

XML:

<interface>
   <field id="button_selected"
      type="assocarray"
      alias="dialog.buttonSelected"
   />
</interface>
<children>
   <Dialog
   id="dialog"
   />
</children>
</component> 

BRS:

print m.top.observeField("button_selected", "onButtonSelected")

I tried a quick test trying to add it to the code you have, but I couldn't come up with the right way to specify it or I had some other problem with the code since it's not complete.

As for observeField vs observeFieldScoped, I've wondered the same thing, but I've never taken the time to investigate it.

I have to include my standard caveat:  As I've stated many times, I'm not the person to ask about scene graph as I absolutely hate it.  Maybe if I wasted took the time to learn more than the bare minimum I wouldn't hate it so much, but I don't see that ever happening.