The slow cranking could be a result of damaged piston rings. Again, removing the head and conducting inspection is the only way to go for now. If the stator's blue and yellow wires resistance is open then there should not be any voltage output from the same. The fact, you are getting output voltage there should be some kind of continuity on those yellow and blue wires meaning there should be some resistance. As for the charging system, if the hot wire output of the rectifier is connected directly to ground it will damage the rectifier leaving it as an open ckt thus it should not damage the charging coil of the stator. The resistance of the charging ckt is really low almost 0.5 ohms while the power ckt is between 680~800 ohms. Remember, the power ckt of the stator needs some good cranking speed to attain 180+ peak voltage if read on a DVA or 110~130 Volts RMS when read with a regular DVM.