Bell;
With Ign ON, when Points are open, you
should measure 12V on that node! Remember, you measure V across the open switch of a circuit which has V supplied and where the switch is on the low side, supplying the return current path. ...and that is precisely the situation we have in the Ign Coil circuit.
Cheers
Edit: ...and to part two of your description...if you are seeing sparks at the Points when cranking, that is rather expected and not unusual (the Ign Condensor minimizes but does not eliminate them entirely)...in that case you should also get HiV sparks from the Ign Coil secondary (which then must "distributed" and sent to the correct Sp Plug)...