I have a Graintrak monitor on a R62 with the moisture sensor installed on the top of the bin loader and haven't had any trouble. If you put the sensor in the middle of tube you have to cut some of fliting off of the auger and it will make the auger go out of balance.
Is the bin bin loader auger on your R62 tapered on the outlet endIJ I only used mine on wheat and when I would get into an area of weeds or wetter wheat it would build up on the sensor until the load was above the auger. Moisture would be accurate until then but would register 40 - 50% until the sensor was cleaner off. I haven't used it yet in corn or millets to see if it is an isolated problem. The taper in the auger flighting starts just where the sensor starts to pick up the grain. I feel this prevents the grain from being pushed through the sensor.
My auger on the R62 is not tapered on the end I have a sheild to force the grain to go over the sensor on the front side of the auger with sensor mounted on the bottom . Once in a while in soybeans I have build up on the sensor giving me a high moisture reading . I just stop and clean it off once in a while it does not happen very often. I have never had a problem in corn.