There is actually another issue with the Potentiometer library : its usage of pins. If Wiring adopts the usual convention to number analog pins A0-A5 etc.
Potentiometer should make use of "A0" for pin numbers. This has a number of implications, because for example an Arduino MEGA
Another mistake : there is a hard definition
#define POTENTIOMETER_ADC_RESOLUTION 1024
that makes the library HW dependent... The Maple, that _should_ :-( be supported by Wiring, has a 12 bit resolution...
So this definition should make a reference to some board.txt file.