The answer to your first question is no. The Pfalzgraf bei Rhein was simply the title of the prince of the Pfalz, a region in southwest Germany. All the four wordly Kurfürsten (electors) held different titles: Markgraf (Brandenburg), König (Böhmen), Herzog (Sachsen), and Pfalzgraf (Pfalz). All of these titles existed in other territories, too, hence the distinsction by territory: Markgrave of Brandenburg, Duke of Saxonia, King of Bohemia and Count Palatine of the Rhine. As for the second question: In general a count palatine means that he was responsible for a royal residence (Pfalz). In so far there were a lot of count palatines, who differ from regular counts by governing a territory that belonged to the king, not some other nobleman. The Counts Palatine of the Rhine were special in so far that the territory eventually grew so big (simplified said by being given to a family, the Wittelsbach, who held a lot of land even before that and united that with the land that already belonged to the "office" of the Count Palatine) that they were considered among the most important in the HRE. When it came to chosing the electors in 1356 Emperor Charles IV. had to give one of the votes to the Wittelsbach family as one of the most powerful ones. Since the Duke of Bavaria, also of the Wittelsbach family, had been his adversary for a long time the Palatine branch ended up with the elector's seat. Edit: Karl Kroeschell: Deutsche Rechtsgeschichte would be the go to book on this. I do not know whether an English translation exists.