I followed my prior info on setting nicknames, after adding 4 more sensors, and I too could not nickname the new sensors. After a lot of trial and error, I found a success route. Under the Real Data tab, while reading the sensors, click on the sensor, fill in the upper and lower setting with a C number (I used 100 for the upper and 0 for the lower, corresponding to 212F and 32F), add the nickname, click OK, and I got a report of "success." Repeat for each sensor. Doing this I successfully added nicknames for the 4 new sensors.